Pressure compensation members, emitters, drip line and methods relating to same

ABSTRACT

A pressure compensation member, an irrigation drip emitter, drip lines and methods relating to same, are provided for delivering irrigation water from a supply tube to an emitter outlet at a reduced and relatively constant flow rate. The pressure compensation member being suitable for use in conventional emitters or alternate emitters being provided having either a uniform elastomeric emitter body configuration or a poly-material emitter body utilizing an elastomeric pressure compensation member. Various methods are also disclosed herein relating to the pressure compensation member, emitters and/or drip line using such pressure compensating members and/or emitters.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.15/881,285, filed Jan. 26, 2018, which claims the benefit of U.S.Provisional Application No. 62/451,541, filed Jan. 27, 2017 and U.S.Provisional Application No. 62/510,458, filed May 24, 2017, which arehereby incorporated herein by reference in their entirety.

FIELD

The present invention relates to irrigation drip emitters, and moreparticularly, to pressure compensation members for same, to uniformelastomeric emitters, to poly-material emitters, to multiple irrigationdrip emitters mounted to a supply tube to form an irrigation drip lineassembly and methods relating to same.

BACKGROUND

Drip emitters are commonly used in irrigation systems to convert waterflowing through a supply tube at a relatively high flow rate to arelatively low flow rate at the outlet of each emitter. Each dripemitter generally includes a housing defining a flow path that reduceshigh pressure water entering the drip emitter into relatively lowpressure water exiting the drip emitter. Multiple drip emitters arecommonly mounted on the inside or outside of a water supply tube. In onetype of system, a large number of drip emitters are mounted at regularand predetermined intervals along the length of the supply tube todistribute water at precise points to surrounding land and vegetation.These emitters may either be mounted internally (i.e., in-line emitters)or externally (i.e., on-line or branch emitters). Some advantages toin-line emitters are that the emitter units are less susceptible tobeing knocked loose from the fluid carrying conduit and the conduit canbe buried underground if desired (i.e., subsurface emitters) whichfurther makes it difficult for the emitter to be inadvertently damaged(e.g., by way of being hit or kicked by a person, hit by a lawnmower ortrimmer, etc.).

In addition to the advantages of in-line emitters, subsurface dripemitters provide numerous advantages over drip emitters located andinstalled above ground. First, they limit water loss due to runoff andevaporation and thereby provide significant savings in waterconsumption. Water may also be used more economically by directing it atprecise locations of the root systems of plants or other desiredsubsurface locations.

Second, subsurface drip emitters provide convenience. They allow theuser to irrigate the surrounding terrain at any time of day or nightwithout restriction. For example, such emitters may be used to waterpark or school grounds at any desired time. Drip emitters located aboveground, on the other hand, may be undesirable at parks and schoolgrounds during daytime hours when children or other individuals arepresent.

Third, subsurface emitters are not easily vandalized, given theirinstallation in a relatively inaccessible location, i.e., underground.Thus, use of such subsurface emitters results in reduced costsassociated with replacing vandalized equipment and with monitoring forthe occurrence of such vandalism. For instance, use of subsurfaceemitters may lessen the costs associated with maintenance of publiclyaccessible areas, such as parks, school grounds, and landscaping aroundcommercial buildings and parking lots.

Fourth, the use of subsurface drip emitters can prevent the distributionof water to undesired terrain, such as roadways and walkways. Morespecifically, the use of subsurface drip emitters prevents undesirable“overspray.” In contrast, above-ground emitters often generate overspraythat disturbs vehicles and/or pedestrians. The above-identifiedadvantages are only illustrative; other advantages exist in connectionwith the use of subsurface drip emitters.

Although some advantages of subsurface emitters are described above, itwould be desirable to provide an improved in-line drip emitter designthat can be used in both subsurface and above ground applications. Forboth applications, there is a need to provide for a relatively constantwater output from each of the emitters in the irrigation system. Morespecifically, it is desirable to provide pressure compensation so as toensure that the flow rate of the first emitter in the system issubstantially the same as the last emitter in the system. Without suchflow rate compensation, the last emitter in a series of emitters willexperience a greater pressure loss than the first. Such pressure lossresults in the inefficient and wasteful use of water.

There is also a need in the irrigation industry to keep drip emittersfor both subsurface and above ground applications from becomingobstructed, which results in insufficient water distribution andpotential plant death. Obstruction of an emitter may result from theintroduction of grit, debris, or other particulate matter from debrisentering the emitter through the supply tube. It is therefore desirableto have an inlet and/or other structures that are of a design to deflectparticles that might otherwise clog flow passages in the body of theemitter. The flow through area of the inlet, however, must also be largeenough to allow proper functioning of the drip emitter. A need alsoexists for better emitter designs that help prevent clogging and improveflushing of grit so that desired flow rates can be achieved andmaintained.

It is also desirable to provide a drip emitter that minimizes parts andassembly as this will not only make the component less complicated toconstruct and likely save on material costs, but will also reduce thenumber of emitters that do not perform as desired due to misalignedparts, etc. Drip emitters are commonly formed of multi-piece components(e.g., two or more-piece housing structures with separate flexiblediaphragms, etc.) that require individual manufacture of the variousparts of the emitter and then assembly of the parts prior to mounting tothe supply tube. Even slight misalignment of these components duringassembly may result in a malfunctioning drip emitter. Thus, in additionto the above needs, it would be desirable to reduce the number ofcomponents required to make the emitter and the manufacturing steps andtime it takes to create a finished product.

It is also desirable to provide a drip emitter that minimizes the amountof disturbance the emitter causes to the fluid flowing through the dripline or conduit to which the emitter is connected. Larger cylindricalemitters are available in the marketplace for in-line emitterapplications, however, these emitters interfere with the flow of thefluid traveling through the drip line or tube and introduce moreturbulence to the fluid or system due to the fact they cover and extendinward from the entire inner surface of the drip line or tube. Theincreased mass of the cylindrical unit and the fact it extends about theentire inner surface of the drip line or tube also increases thelikelihood that the emitter will get clogged with grit or otherparticulates (which are more typically present at the wall portion ofthe tube than in the middle of the tube) and/or that the emitter itselfwill form a surface upon which grit or particulates will build-up oninside the drip line and slow the flow of fluid through the drip line orreduce the efficiency of this fluid flow. Thus, there is also a need toreduce the size of in-line emitters and improve the efficiency of thesystems within which these items are mounted.

It is also desirable to provide a drip line that can be buriedsub-surface and/or under surface coverings such as bark or mulch withoutbeing interfered with by obstructions such as roots, grit, etc.Conventional emitters typically have difficulty in being used in atleast sub-surface applications due to root obstruction that occurs fromplants or vegetation growing toward the emitter creating an obstructionto the normal flow of fluid through the emitter. In the past, chemicalshave been devised for use with sub-surface irrigation equipment toinhibit such root growth/interference, but these chemicals are eitherexpensive to use or damaging to other materials used in the irrigationsystem (e.g., tubing, couplings, valves, the emitter itself, etc.).

Another problem with conventional emitters and drip line is that theyrequire the use of complex structures to regulate pressure and/or do notflush grit through the emitter in a way that makes the emitter moreuniversally acceptable for broad applications. Often the complexstructures drive up component cost, thereby pricing the component out ofthe market. Other times (or in addition) the complex structuresneedlessly complicate the emitter's grit tolerance.

An additional problem associated with conventional emitters relates tobonding such emitters to the inside surface of drip line tubing. Somehave tried to address this problem by using a two-shot process formolding a bi-material emitter consisting of a rigid body formed by afirst shot molding process and an elastomeric membrane formed by asecond shot molding process. For example, U.S. Pat. No. 5,203,503 issuedApr. 20, 1993 to Cohen, now expired, discloses the use of a single moldand a two-shot molding process for forming a bi-material emitter. Otherattempts at utilizing such a two-shot molding process to form abi-material emitter have been pursued, (e.g., U.S. Pat. No. 8,372,326issued Feb. 12, 2013 to Mamo, and U.S. Pat. No. 8,317,112 issued Nov.27, 2012), but these require complex manufacturing processes whichrequire cross-linking between materials or use of thermoset elastomericcomponents that require interlocking features to secure the elastomericcomponent to the surrounding rigid structure, respectively.

Accordingly, it has been determined that the need exists for improvedpressure compensation members, an improved in-line emitter and methodsrelating to same which overcomes the aforementioned limitations andwhich further provides capabilities, features and functions, notavailable in current designs and methods, and for an improved method fordoing the same.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of severalembodiments of the present invention will be more apparent from thefollowing more particular description thereof, presented in conjunctionwith the following drawings.

FIGS. 1A-F are perspective, top, left-side elevation, right-sideelevation, bottom and front views, respectively, of a drip emitterembodying features of the present invention, with the perspective andfront views illustrating the emitter bonded to the inner side of a dripline or tube (shown in broken line), the opposite end view (i.e., rearview) being a mirror image of the end view illustrated;

FIGS. 1G-H are cross-sectional views of the emitter of FIGS. 1A-F takenalong line i-i illustrated in FIG. 1B, with FIG. 1G illustrating thetapered portion of the inner baffle wall at its low pressure position toshow how fluid can flow over the top thereof, and FIG. 1H illustratingthe tapered portion of the inner baffle wall at its high pressureposition to show how fluid is prevented from flowing over the topthereof;

FIGS. 1I-J are charts illustrating the amount of deflection of thetapered portion of the inner baffle wall per increase in pressure atpoints 1 and 2 along the tapered portion as illustrated in FIG. 1B, withFIG. 1I illustrating deflection vs. pressure for an elastomeric emitterbody material having a Durometer value of 50 and FIG. 1J illustratingdeflection vs. pressure for an elastomeric emitter body material havinga Durometer value of 75;

FIGS. 2A-D are perspective, top, right-side elevation, and left-sideelevation views, respectively, of an alternate drip emitter embodyingfeatures of the present invention wherein a tongue and fork typearrangement is used instead of a single tapered portion to compensatefor pressure fluctuations that the emitter is exposed to when insertedin a supply line, the end and bottom views of this embodiment lookingsimilar to those of the embodiment of FIGS. 1A-F;

FIGS. 2E-F are cross-sectional views of the emitter of FIGS. 2A-D takenalong line i-i illustrated in FIG. 2B, with FIG. 2E illustrating thetongue and fork arrangement at their low pressure position to show howfluid can flow over the top thereof, and FIG. 2F illustrating the tongueand fork arrangement at their high pressure position to show how fluidis restricted from flowing over the top thereof;

FIGS. 3A-D are perspective, top, left-side elevation and right-sideelevation views, respectively, of an alternate drip emitter embodyingfeatures of the present invention wherein inlet openings of varyingheights are used to compensate for pressure fluctuations that theemitter is exposed to when inserted in a supply line;

FIGS. 3E, F and G are additional right-side elevation, bottom andperspective views, respectively, of the embodiment of FIGS. 3A-D whereinFIG. 3E illustrates the inlet opening sleeves at a higher pressureposition showing at least some of the inlet openings being closed tocompensate for an increase in pressure and FIG. 3G illustrates theembodiment of FIGS. 3A-D from a rear left perspective instead of thefront right perspective illustrated in FIG. 3A;

FIG. 4 is a perspective view of an alternate drip emitter and drip lineembodying features of the present invention and illustrating an emitterwith a baffle design which opens and closes in a non-sequential manner;

FIGS. 5A-B are perspective views of an alternate drip emitter and dripline embodying features of the present invention with FIG. 5Aillustrating the emitter partially disposed in a drip line tube andwherein the pressure-reducing flow channel is made-up of baffles withflexible teeth that move in response to fluid flow through the emitterbody;

FIG. 6A is a perspective view of an alternate drip emitter and drip lineembodying features of the present invention wherein thepressure-reducing flow channel is made-up of baffles with hollow teethor teeth that enlarge as fluid pressure increases within the supply lineso that the pressure-reducing flow channel has a first cross-section atlower fluid pressures and a second cross-section, smaller than thefirst, at higher fluid pressures to compensate for the increase in fluidpressure so that the emitter and drip line trickle fluid at a generallyconstant or desired rate;

FIGS. 6B-C are perspective views of a portion of the flow channel ofFIG. 6A illustrating the hollow teeth of the baffle partially enlargedand fully enlarged, respectively, in response to increasing fluidpressure showing how the cross-section of the pressure-reducing flowchannel in FIG. 6B has a smaller cross-section than that illustrated inFIG. 6A due to an increase in fluid pressure and showing how thecross-section of the pressure-reducing flow channel of FIG. 6C is evensmaller yet than that illustrated in FIG. 6B due to a further increasein fluid pressure;

FIG. 6D is a perspective view of a portion of the bottom of the emitterillustrated in FIG. 6A showing the underside of the hollow teeth membersof the baffle and how such surfaces are exposed to the fluid and areaffected by an increase in fluid pressure;

FIGS. 7A-B are perspective and perspective cross-sectional views,respectively, of another emitter embodying features of the presentinvention wherein a unitary body defines first and second wallsinterconnected together to form a pressure reduction flow channel, thecross-section being taken along lines ii-ii in FIG. 7A;

FIG. 7C-D are top plan and top cross-sectional views, respectively, ofthe emitter of FIGS. 7A-B, with the cross-section being taken alonglines v-v of FIG. 7H;

FIG. 7E is a bottom perspective view of the emitter of FIGS. 7A-Dillustrating how the first and second walls form a generally curvedchannel that increases of pressure will act upon to press the first andsecond walls toward one another to further restrict fluid flow;

FIGS. 7F-G are right-side elevation and right-side cross-sectionalviews, respectively, of the emitter of FIGS. 7A-E illustrating one formof the first and second walls that combine to restrict fluid flowthrough the emitter, the cross-section being taken along lines iii-iiiin FIG. 7C;

FIGS. 7H-I are front elevation and front cross-sectional views,respectively, illustrating the emitter body shape and shape of the firstand second walls and the interconnection therebetween, the cross-sectionbeing taken along lines iv-iv in FIG. 7F;

FIGS. 8A-B are perspective and perspective cross-sectional views,respectively, of another emitter embodying features of the presentinvention wherein a unitary body defines a series of rows of bafflestransverse to the longitudinal axis of the emitter and extending intothe pressure reduction flow path, with a portion of the baffles varyingin height to create a structure that compensates for pressure, thecross-section being taken along line vi-vi in FIG. 8A;

FIGS. 8C-E are top plan, front elevation and bottom perspective views,respectively, of the emitter of FIGS. 8A-B;

FIGS. 8F-G are left-side elevation and left-side cross-sectional views,respectively, of the emitter of FIGS. 8A-E, the cross-section beingtaken along line vii-vii in FIG. 8C; and

FIGS. 9A-B are top and bottom perspective views, respectively, ofanother emitter embodying features of the present invention wherein aunitary body defines a series of rows of baffles transverse to thelongitudinal axis of the emitter and extending into the pressurereduction flow path, and a plurality of outlet baths with at least aportion of outlet passage being moveable between first and secondpositions, the second position defining a fluid passage that is moreconstrictive than the first position;

FIGS. 10A-E are perspective, cross-sectional, left-side elevation, topplan and front elevation views, respectively, of an alternate emitterembodying features of the present invention wherein a unitaryelastomeric body defines an inlet, pressure reduction and compensationsection and an outlet bath having a root inhibitor member for disruptingroot growth that could interfere with the operation of the emitter (FIG.10E further illustrating the emitter mounted in a drip line or tube);

FIGS. 11A-E are perspective, cross-sectional, left-side elevation, topplan and front elevation views, respectively, of another emitterembodying features of the present invention wherein a unitaryelastomeric body defines an inlet, pressure reduction and compensationsection and an outlet bath having a root inhibitor member for disruptingroot growth that could interfere with the operation of the emitter;

FIGS. 12A-B are top and bottom perspective views, respectively, of analternate emitter embodying features of the present invention wherein aunitary elastomeric body defines an inlet, pressure reduction andcompensation section and outlet bath having an alternate pressurecompensation design with the root growth inhibitor exploded from theemitter body in FIG. 12A;

FIGS. 13A-B are top and bottom perspective views, respectively, of anemitter embodying features of the present invention wherein a unitaryelastomeric body is illustrated with an alternate inlet, flow path andoutlet, with the root growth inhibitor exploded from the emitter body inFIG. 13A;

FIGS. 14A-B are top and bottom perspective views, respectively, of anemitter embodying features of the present invention wherein a unitaryelastomeric body is illustrated with an inlet and another flow path andoutlet, with the root growth inhibitor exploded from the emitter body inFIG. 14A;

FIGS. 15A-B are top and bottom perspective views, respectively, of anemitter embodying features of the present invention wherein a unitaryelastomeric body is illustrated with an alternate inlet, flow path andoutlet and having the root growth inhibitor exploded from the emitterbody in FIG. 15A;

FIGS. 16A-B are perspective and cross-sectional views, respectively, ofan emitter embodying features of the present invention wherein a unitaryelastomeric body is illustrated equipped with a carrier for assisting inthe installation of the emitter into tubing, with the cross-section ofFIG. 16B being taken along line 16B-16B in FIG. 16A;

FIGS. 17A-B are perspective and exploded views, respectively, of anemitter embodying features of the present invention wherein the unitaryelastomeric body is illustrated connected to a carrier or bracket inFIG. 17A for assisting in the installation of the emitter into tubingand the carrier or bracket exploded from the emitter body in FIG. 17B;

FIGS. 18A-B are perspective and exploded views, respectively, of anemitter embodying features of the present invention wherein the unitaryelastomeric body is illustrated with a connecting bracket coupled to thebonding side of the elastomeric emitter body in FIG. 18A which may beused to assist in connecting the emitter to drip tubing and explodedfrom the body in FIG. 18B;

FIGS. 19A-C are perspective, side cross-section and end cross-sectionviews, respectively, of another emitter in accordance with an embodimentof the invention disclosed herein, with a root growth inhibitor insertexploded from the emitter in FIG. 19A, the left-side cross-section viewof FIG. 19B taken along line B-B in FIG. 19A and the end cross-sectionview of FIG. 19C taken along line C-C in FIG. 19A;

FIGS. 20A-B are perspective and exploded views, respectively, of anotherexemplary emitter in accordance with an embodiment of the inventiondisclosed herein;

FIGS. 21A-E are perspective, top, bottom, right and left side elevationviews, respectively, of an elastomeric emitter in accordance withembodiments of the invention;

FIGS. 22A-E are perspective, top, bottom, right and left side elevationviews, respectively, of an elastomeric emitter in accordance withembodiments of the invention;

FIGS. 23A-E are perspective, top, bottom, right and left side elevationviews, respectively, of an elastomeric emitter in accordance withembodiments of the invention;

FIGS. 24A-D are perspective, top, bottom and left side elevation views,respectively, of another elastomeric emitter in accordance withembodiments of the invention;

FIGS. 24E-F are left-side cross-sectional and front cross-sectionalviews of the emitter of FIGS. 24A-D taken along line A-A and line B-B ofFIG. 24A, respectively;

FIGS. 25A-B are left-side elevation and bottom views of an elastomericemitter in accordance with embodiments of the invention illustratingeight protrusions that may be used to assist in removal of the emitterfrom a mold and/or transport the emitter through insertion tooling;

FIG. 26 is a left-side elevation view of an elastomeric emitter inaccordance with embodiments of the invention and illustrating twoprotrusions that may be used to assist in removal of the emitter from amold and/or transport the emitter through insertion tooling;

FIGS. 27A-J are top perspective, right-side elevation, right-sidecross-sectional taken along line 27C-27C in FIG. 27A, left-sideelevation, left-side cross-sectional taken along line 27E-27E in FIG.27A, bottom perspective, top, bottom, front elevation and rear elevationviews, respectively, of another elastomeric emitter in accordance withembodiments of the invention;

FIGS. 28A-J are top perspective, exploded, right-side elevation,left-side elevation, left-side cross-sectional view taken along line28E-28E in FIG. 28A, front elevation, rear elevation, top, bottom andbottom perspective views, respectively, of an alternate bi-materialemitter in accordance with embodiments of the invention; and

FIGS. 29A-H are top perspective, exploded, right side elevation, leftside elevation, top, bottom, bottom perspective and perspectivecross-sectional views, respectively, of another bi-material emitter inaccordance with embodiments of the invention with the perspectivecross-sectional view taken along line 29H-29H in FIG. 29A.

Corresponding reference characters indicate corresponding componentsthroughout the several views of the drawings. Skilled artisans willappreciate that elements in the figures are illustrated for simplicityand clarity and have not necessarily been drawn to scale. For example,the dimensions of some of the elements in the figures may be exaggeratedrelative to other elements to help to improve understanding of variousembodiments of the present invention. Also, common but well-understoodelements that are useful or necessary in a commercially feasibleembodiment are often not depicted in order to facilitate a lessobstructed view of these various embodiments of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIGS. 1A-F, a drip irrigation emitter 10 is provided fordistributing water from a fluid supply source or conduit, such as dripline or tube 70, at a low flow rate. The drip line 70 carriespressurized fluid throughout an irrigation system and preferablyincludes numerous emitters 10 spaced apart at predetermined intervals inthe dip line 70 in order to allow the drip line 70 to be placed above orbelow ground to water and/or treat grass, plants, shrubs, trees or otherlandscaping, or to water agricultural crops of various kinds. In theform illustrated, the emitter 10 includes an integral body 20 whichdefines an inlet 30 connectible to a source of pressurized fluid, anoutlet 40 for discharging the fluid from the emitter body 20, and apressure reducing flow channel or passage 50 between the inlet 30 andoutlet area 40 for reducing the flow of fluid discharged through theoutlet 16. In addition, the emitter body 20 defines a pressurecompensating member 60 for reducing a cross-section of the flow channelin response to an increase in pressure of the pressurized supply linefluid.

In the form illustrated, the emitter body 20 is made of an elastomericmaterial, such as a thermoplastic or thermosetting elastomeric materiallike materials that use ethylene, propylene, styrene, PVC, nitrile,natural rubber, silicone, etc., to form a polymer or copolymer. In apreferred form, the elastomeric material is made of thermoplasticpolyolefin (TPO) and silicone rubber. This combination helps create anemitter and drip line that is capable of withstanding the hightemperatures and harsh chemicals the emitter may be subjected to whilein use. In addition, the emitter is made of a singular or unitaryconstruction rather than having a multi-part construction and/orrequiring the assembly of housing parts, diaphragms, etc. This simpleconstruction makes it easier to manufacture the emitter and makes theemitter more grit-tolerant. More particularly, the simple and flexibleconstruction of the emitter can easily process grit or otherparticulates by expanding to process the grit (aka burping) due to thefact there are no additional housing portions to prevent such expansion.This simple construction also allows the emitter to be flushed moreeasily by allowing line pressure to be increased to process grit out ofthe emitter without concern for damaging the emitter because there areno additional pieces, such as multi-part housings, that limit the amountof movement the emitter can make before breaking or coming apart.

Whereas in conventional emitters, even those having two-piece housings,diaphragms and metering grooves to assist in the flushing of grit, theemitter typically reaches a state where further increases is pressurewill not increase processing of grit. For example, in conventionalemitters, at a certain point of fluid pressure, the pressure on bothsides of the diaphragm will eventually become equal and the emitter willcease processing or burping the grit. In the form illustrated, however,the disclosed emitter will continue to process grit with increases inpressure well beyond when conventional emitters stop processing grit(e.g., when this state of equal pressures on opposite sides of thediaphragm are reached). Thus, line pressure can simply continue to beincreased in order to drive grit through the emitter body. Theelastomeric nature of the emitter body 20 further helps flushing orburping particulates or grit even when simply turning on and off thesupply line.

As best illustrated in FIGS. 1E-F, the body 20 defines a plurality ofslots 21, 22, 23 and 24, extending longitudinally along the bottomsurface of the emitter body 20 which are separated by protrusions, suchas guide ribs 25, 26, 27, 28 and 29. The outer most guide ribs 25 and 29are positioned on the periphery of the bottom surface of emitter body 20while the inner most ribs 26-28 are positioned on an interior portionseparated from the periphery by inlet channel 31. In a preferred form,the inlet channel 31 is sized to deflect foreign materials fromobstructing the inlet 30 or entering the emitter body 20 and guide ribs25-29 have at least one tapered end and run parallel to the longitudinalaxis of the emitter body 20 to further help deflect foreign materialsfrom obstructing the inlet channel 31 or entering the emitter body 20.In the form illustrated, the inlet channel 31 extends continuouslyaround or at a perimeter region of the emitter body 20 and empties intothe inlet 30. More particularly, in the form illustrated, the inletchannel 31 is a generally oval shaped raceway recessed in the bottomsurface of the emitter body 20 having curved ends 31 a, 31 b and longerstraight-aways 31 c, 31 d that run longitudinally along the bottom ofbody 20. The inlet channel has a generally rectangular cross-section andopens into the inlet 30 via a rectangular shaped opening.

The recessed nature and length of inlet channel 31 helps prevent grit orother particulates from entering into the inlet 30 that could clog theemitter 10 or form obstructions preventing the emitter 10 from operatingin the desired manner. More particularly, once installed in the dripline 70, pressurized fluid flows along the bottom side of the emitterbody 20 with some fluid entering into the raceway of inlet channel 31and traveling about the periphery of the emitter body 20 and then,ultimately, into the inlet opening 30. In this manner, the side walls ofchannel 31 serve to deflect grit and other particulates in the fluidfrom entering into the inlet channel 31 and into the inlet opening 30.This prevents the emitter 10 from getting clogged and/or havingobstructions enter the emitter 10 that might otherwise negatively affector compromise the desired operation of the emitter. The circular flowthat is created by the inlet channel 31 further helps ensure that largerparticulates that might fit within the inlet channel 31 will fall out ofor be flushed from the channel 31 as the fluid races about the racewaybefore the fluid enters into the inlet opening 30.

The guide ribs 25-29 serve the dual function of assisting with themounting of the emitter body 20 into the irrigation drip line andfurther help deflect grit or particulates in the pressurized fluid awayfrom the inlet channel 31 and inlet opening 30. More particularly, oneor more of the guide ribs 25-29 may be used by an insertion tool toalign and insert the emitter body 20 into the drip line 70 as the dripline is being extruded. In a preferred form, this is done as the dripline 70 is being extruded so that the upper surfaces of the emitter body20 are bonded or welded to the drip line 70 while the drip line is hotand before it begins to cool. The guide ribs 25-29 may also be taperedor pointed to assist in the initial loading of the emitter body 20 froma bowl sorter and into the inserter or loader used to insert the emitterbody 20 into the freshly extruded drip line 70. Such tapering furtherassists with getting fluid in the supply line to flow between the narrowpassages defined by the ribs 25-29 without causing too much disturbanceor adding too much turbulence to the fluid flowing through the supplyline 70.

In the form illustrated, the guide ribs 25-29 also help prevent grit orother particulates in the pressurized fluid from entering into the inletchannel 31 and inlet opening 30. More particularly, like the sidewallsof inlet channel 31, the ribs 25-29 create narrowed passageways whichhelp deflect larger particulates away from the inlet channel 31 andinlet opening 30. Thus, the ribs 25-29 deflect away larger particulatesfrom the inlet channel 31 and inlet opening 30 and the sidewalls ofinlet channel 31 deflect away smaller particulates that are capable offitting into the narrowed passageways defined by the ribs 25-29. Thisprevents the emitter 10 from getting clogged and/or having obstructionsenter the emitter 10 that might otherwise negatively affect orcompromise the desired operation of the emitter 10.

In the form illustrated, the inlet opening 30 is generally rectangularin shape and of a desired size to ensure that the emitter 10 receives adesired amount of fluid at a desired fluid flow rate in order to operateas desired. In alternate forms, however, the inlet opening 30 may bedesigned in a variety of different shapes and sizes to accommodatespecific desires or applications. For example, in alternate forms, theinlet opening may be designed as more of an elongated slot or slit, orplurality of slot-like openings as illustrated in FIG. 4 (which will bediscussed further below), for receiving fluid but further deflectinggrit or particulates that are small enough to pass through the walls ofinlet channel 31 or it may be designed to cooperate with thepressure-reduction flow channel 50 to start reducing the flow andpressure of the fluid as it enters the emitter body 20 (e.g., the inletmay form a tortuous passage that leads to the pressure-reduction channel50). Similarly, the inlet channel 31 may be designed in a variety ofdifferent shapes and sizes. For example, instead of a generally ovalshape, the inlet channel 31 may be designed to be a smaller slot thatextends over a small portion of emitter body 20 instead of travelingabout a periphery of the bottom of the emitter body 20, or may bedesigned with a zigzag pattern to form a tortuous path to further assistin reducing pressure of the fluid passing through the emitter body 20(similar to that of the flow path 50, which will now be discussed infurther detail).

With respect to the fluid that makes it through the passageways definedby ribs 25-29 and into the inlet channel 31, this fluid passes throughthe inlet opening 30 and enters a pressure-reducing flow channel 50 thatproduces a significant reduction in pressure between the fluid flowingin the primary lumen of the supply conduit or drip line 70 and the fluidultimately emptying into and present in the emitter outlet area 40. Inthe form illustrated, the emitter body 20 defines opposed baffle wallsto create the pressure-reducing flow channel and, in a preferred form,has an inner baffle wall 51 that is surrounded by an outer baffle wall52 which extends about the inner baffle wall 51 in a generally U-shapedmanner to form a flow passageway that generally directs the water in aU-shaped direction of travel. More particularly, the inner and outerbaffle walls 51, 52 have alternating projections and recesses that forma tortuous passage and cause the fluid flowing therethrough to zigzagback and forth, reducing pressure with each turn the fluid makes. Theouter baffle wall 52 is defined by an outer rim or peripheral wall ofthe emitter body 20 and the inner baffle wall 51 extends from a portionof the outer rim or peripheral wall and into to the middle of theemitter body 20 to form a peninsula about which the fluid flows frominlet 30 to outlet 40. The upper surfaces of the emitter body preferablyhave a radius of curvature that tracks the radius of curvature of thetube 70 so that the emitter body 20 can be bonded securely to the innerwall of the tube 70 and create an enclosed pressure reduction passagefrom inlet 30 to outlet 40. In the form illustrated, the tortuouspassage is formed via alternating teeth extending from opposing surfacesof the inner and outer baffle walls 51, 52 and has a cross-section thatis generally rectangular in shape when the emitter body 20 is bonded tothe inner surface of the extruded drip line 70 (keeping in mind that theradius of curvature of the tube 70 will likely make the upper portion ofthe cross-section slightly curved and the side walls to be slightlywider at their top than at their bottom).

It should be understood, however, that in alternate embodiments, thepressure-reducing flow channel 50 may be made in a variety of differentshapes and sizes. For example, instead of having projections withpointed teeth, the baffles could be made with blunt or truncated teeth,with teeth that are angled or tapered, with curved or squaredprojections instead of triangular shaped teeth, with projections ofother geometrical shapes or geometries, symmetric or asymmetric, etc.

In the form illustrated, the pressure-reducing flow channel 50 alsoincludes an intermediate bath 53 that the fluid pours into as it makesthe turn in the generally U-shaped direction of travel which furthercauses pressure reduction as the water is flowing from a smaller passageto a larger passage in the bath 53. After making the turn, the fluidpasses or zigzags through another section of the pressure-reducing flowchannel 50 and empties into outlet pool 40.

In addition to the pressure-reducing flow path 50, the emitter 10further includes a pressure compensating feature 60 which further allowsthe emitter 10 to compensate for increases in fluid pressure in theprimary lumen of the tube 70. More particularly, pressure compensatingfeature 60 allows the emitter 10 to maintain relatively constant outletfluid flow and pressure even though the inlet fluid pressure mayfluctuate from time-to-time. In the form illustrated, the pressurecompensating feature 60 is a two part pressure compensation mechanismthat comprises an elastomeric portion 61 capable of deflecting underpressure to reduce the cross-section of the pressure-reducing flowchannel 50 and regulate fluid flow through the emitter, and a moveablebaffle portion 62 capable of changing the length of the flow channel tocompensate for changes in supply line 70 fluid pressure.

The elastomeric portion 61 being a deflectable portion of the emitterbody 20 that is moveable between a first position wherein at least aportion of the pressure-reducing flow channel 50 is of a firstcross-section and a second position wherein the at least a portion ofthe pressure-reducing flow channel 50 is of a second cross-section,smaller than the first cross-section to regulate fluid flow through theemitter. In the form illustrated, the floor 61 of the flow channel 50forms an elastomeric portion and raises and lowers in response toincreases and decreases in supply line 70 fluid pressure, respectively.Thus, when fluid pressure increases in the supply line 70, the floor 61of the flow channel 50 is pressed-up or deflected up into the flowchannel 50 thereby reducing the cross-section of the flow channel toregulate the flow of fluid through the emitter 10. Conversely, whenfluid pressure in the supply line 70 reduces, the floor of the flowchannel 50 retreats from the flow channel back to a normal positionwherein the floor is not deflected up into the flow channel therebyincreasing the cross-section of the flow channel to allow fluid to flowmore freely through the flow channel 50.

Although the above embodiment has been described with the floor of theflow path 50 deflecting up into the emitter flow path to reducecross-section size of the flow path to compensate for increases in fluidpressure, it should be understood that in alternate embodiments, otheremitter surfaces could be designed to either create this deflection ontheir own or to cooperate with the floor or other surface so that bothdeflect in order to compensate for fluid pressure increases. Forexample, rather than having the floor deflect, the side walls and/orceiling of the flow channel 50 could be designed to deflect either incombination with any one of these items or on their own as the soledeflecting portion.

The second part of the pressure compensation mechanism 60 comprises amoveable structure, such as moveable baffle portion 62, which is capableof moving between a first low pressure position wherein the length ofthe flow channel 50 is of a first distance and a second high pressureposition wherein the length of the flow channel 50 is of a seconddistance wherein the length of the flow channel is longer than the firstdistance to compensate for increase pressure in the supply line 70. Moreparticularly, in the form illustrated, the moveable baffle portion 62deflects up and down with the floor of the flow channel 50 to sealinglyengage and disengage the moveable baffle portion 62 with the inner wallof the supply line 70, respectively, and thereby lengthen or shorten theextent of the flow channel for at least some fluid flowing therethroughto compensate for changes in supply line fluid pressure.

As best illustrated in FIGS. 1C, D and G, the moveable baffle portion 62comprises a tapered portion of the central or inner baffle wall 51 thattapers down away from the inner surface of supply line 70 so that atlower fluid pressures in supply line 70, fluid flows through the inlet30 and first section (or upstream section) of flow channel 50 and thenover the top of the tapered baffle section 62, through the secondsection (or downstream section) of the flow channel 50 and then intooutlet pool 40. Fluid may flow through the remaining portion of the flowchannel 50 including intermediate bath 53 (located between the upstreamand downstream sections of the flow channel 50), but it does not have tonor does all of the fluid flow through these portions of the flowchannel 50 due to the gap between the upper surface of the tapered innerbaffle wall section 52 and the inner surface of tube 70. As fluidpressure increases in the fluid supply line 70, and as best illustratedin FIG. 1H, the floor of the flow channel 50 starts to deflect upwardsand into the flow channel 50 moving the tapered baffle section 62 towardthe inner surface of tube 70 thereby reducing the gap between these twountil the upper surface of the tapered baffle section 62 sealinglyengages the inner wall of the tube 70 thereby preventing fluid fromflowing over the top of the tapered baffle section 62 and lengtheningthe amount of the flow channel 50 through which all of the fluid mustflow and reducing fluid pressure and flow due to same.

The emitter body 20 further defines an outlet area 40 which forms a poolinto which the fluid that passes through inlet 30 and tortuous passage50 and pressure compensation mechanism 60 collects or gathers. An outletin outer supply line 70, such as opening 71, provides access to thefluid collected in the outlet pool 40 and, more particularly, providesan egress for the fluid to trickle or drip out of emitter 10.

Since the emitter 10 is made of an integral body 20, the outlet area 40is provided with obstructions or stops, such as posts or nubs 41, thatprevent the outlet are 40 from collapsing when the fluid pressure ofsupply line 70 raises to a level sufficient for deflecting the floor ofthe flow channel 50 into the flow channel 50 to reduce the cross-sectionof same and regulate fluid flow through the flow channel (or as themoveable structure 62 moves from the first or low pressure position tothe second or high pressure position). In the form illustrated, theposts 41 extend away from the body 20 and are generally frustoconical inshape to make the posts easier to mold when the body 20 is molded. Inaddition, in a preferred form, the upper surfaces of the posts 41 have aradius of curvature common to the radius of curvature of the uppersurfaces of baffles 51, 52 and that corresponds with a second radius ofcurvature of the inner wall of tube 70. The solid nature of the bafflewalls 51, 52 and outer rim or peripheral wall of emitter body 20likewise prevent these portions of the emitter body 20 from collapsingwhen the fluid pressure of supply line 70 pushes the floor of the flowchannel 50 into the flow channel.

Although the form illustrated in FIGS. 1A-D shows the outlet 71 of outertube 70 as a round opening, it should be understood that in alternateembodiments, this may be provided in a variety of different shapes andsizes. For example, in one form, the outer tube outlet 71 may beprovided in the form of a slit, such as an elongated narrow oval shape,instead of a round hole. In other forms, the outer tube outlet 71 mayfurther define a pressure reducing passageway such as a tortuous orzigzag passage.

By using a unitary emitter body 20 to form the inlet 30, flow channel50, outlet 40 and pressure compensating mechanism 60 rather thanrequiring multiple parts to be constructed and assembled to form suchfeatures, the emitter 10 is much easier to manufacture and providessignificant cost savings due to the reduction in parts and materials,and assembly time. The body 20 may be made of any type of materialcapable of allowing for this type of movement for pressure compensation.In a preferred form, however, the body 20 is made of TPO having aDurometer reading ranging between 25 and 100, with the Durometer readingpreferably being between 50 and 75. In FIGS. 1I-J, data is provided forthe amount of deflection per increase in pressure for materials havingDurometer readings of 50 and 75, respectively. In these examples, datawas collected at location points 1 and 2, as indicated in FIG. 1B, withthe distance (or gap) between the inner surface of tube 70 and the uppersurface of the tapered inner baffle wall portion 62 being thirtythousandths of an inch (0.030″) at location point 1 and thirteenthousandths of an inch (0.013″) at location point 2, and the floorthickness of flow channel 50 being eight thousandths of an inch(0.008″). These distances being calculated when the tapered baffle wallportion 62 is at its normal position (or low pressure/non-deflectedposition), as illustrated in FIG. 1G.

As can be seen in comparing FIGS. 1I-J, a quicker movement of thetapered baffle wall portion 62 and corresponding lengthening of the flowchannel 50 can be achieved using a material with a lower Durometerreading (e.g., a softer material), whereas a more constant movement(almost linear at times) of the tapered baffle wall portion 62 may beachieved by using a material with a higher Durometer reading (e.g., aharder material). Thus, the specific application the emitter 10 isintended for may play a role in the material selected for emitter body20 (e.g., if a quicker lengthening of the flow channel 50 is desired amaterial with a lower Durometer reading will be used, whereas if a moregradual closing of the tapered baffle wall portion 62 and more graduallengthening of the flow channel 50 is desired, a material with a higherDurometer reading will be used, etc.).

In order to ensure the consistency of operation for each emitter 10mounted to the extruded supply line 70, care is taken to make sure thatthe various portions of body 20 are constructed with consistentthickness and density from one emitter to the next and that thedistances between location points 1 and 2 and the inner surface ofsupply line 70 are maintained consistently from one emitter to the next.In doing so, the emitters 10 mounted to the supply line 70 shouldoperate in a uniform manner and produce common low pressure fluid flowand flow rates at their respective outputs 40 (e.g., the flow rate ofthe first emitter mounted in the supply line should operate the same asthe last emitter mounted in the supply line).

In an alternate form, the emitter and drip line may be made-up of amulti-part construction and/or use a multi-step manufacturing orassembly process. For example an emitter body of a first type ofmaterial may be combined with another type of material (e.g., astructure, a layer, a coating, etc.) that is more easily bonded toconventional drip tubing so that emitter can be bonded to the tubing ina more consistent manner and each emitter is ensured to work similar toone another. More particularly, since soft materials, such as silicon,do not always bond easily to the various types of conventional drip linetubing used in the industry, which is typically polyethylene tubing, theemitter body may be made-up of a combination of soft and hard materialsto assist in the bonding of the emitter to the extruded tubing and toprovide a process that can repeatedly bond such emitters to extrudedtubing so that there is no significant (if any) variance in bondingbetween the emitters bonded to the tubing.

For example, by combining a soft material like silicon with a hardmaterial like a polyethylene, the hard portion of the emitter may moreeasily be bonded to the extruded tubing in a uniform and repeatablefashion. Although this form of emitter and tubing may be considered bysome to be a two-part construction, it would preferably remainhousingless and the soft portion of the emitter would make up themajority of the component. For example, in one form, the hard portion ofthe emitter would simply comprise a polyethylene coating applied to anupper surface of the emitter to assist in consistently bonding theemitter to the inner surface of the drip line tubing in a manner thatcan be repeated easily from emitter to emitter. Not all of the uppersurfaces of the emitter body need to be coated with the polyethylenecoating and/or connected to the inner surface of the drip line tubing.Thus, in this example, the emitter continues to comprise a singular oruniform structure through which fluid flows that simply has a bondinglayer or agent of polyethylene which assists in connecting the emitterto the inner surface of the drip line tubing. In addition, thisconfiguration would still produce an emitter that can process gritbetter than conventional emitters, including those with multi-parthousings, diaphragms and metering grooves. In alternate forms, truetwo-piece constructions may be used to form the emitter body if desiredwith either piece making up a majority of the structure or bothmaking-up equal portions of the structure and/or either piece or bothmaking up portions of the inlet, flow channel or outlet as desired.

Turning now back to FIGS. 1A-F, a housingless irrigation drip emitter 10is provided for attachment to only a portion of an inner circumferenceof an inner surface of an irrigation drip line tube 70 having anelastomeric emitter body 20 integrally defining an inlet 30 forreceiving pressurized fluid from a fluid supply source, an outlet area40 for discharging the fluid from the body 20, a pressure reducing flowpath 50 extending between the inlet 30 and the outlet area 40 forreducing the pressure and flow of fluid received at the inlet 30 anddischarged through the outlet area 40, and a pressure compensatingportion 60 for automatically adjusting the pressure and fluid flowreducing effect of the flow channel 50 in response to a change inpressure of the fluid supply source 70, wherein the pressure reducingflow channel 50 includes an inner baffle wall 51 and an outer bafflewall 52 that extends about the inner baffle wall 51 in a generallyU-shaped manner. The baffle walls 51, 52 having upper surfaces that havea first radius of curvature that corresponds with a second radius ofcurvature of an inner wall of the irrigation drip line tube 70, and theinner baffle wall 51 having a first portion of constant height and asecond portion 62 of tapering height, the second portion 62 beingmoveable between a first position wherein the upper surface of thesecond portion 62 is not level with the upper surface of the firstportion such that fluid can flow over the upper surface of the secondportion at predetermined low fluid pressures and a second positionwherein the upper surface of at least a portion of the second portion 62is level with the upper surface of the first portion and fluid cannotflow over the level upper surfaces of the second portion 62 such thatthe cross-section of the flow channel is reduced and the length of theflow channel is effectively lengthened.

In the form illustrated, the baffles of the inner and outer baffle walls51, 52 do not close sequentially when the second portion 62 of innerbaffle 51 moves from the first position to the second position, butrather, the teeth of the baffle walls 51, 52 on opposite ends of theflow passage 50 (i.e., some on the inlet end and some on the outlet end)close at the same time. This allows the moving portion 62 of innerbaffle 51 to gradually lengthen the extent of the flow passage 50 assupply line fluid pressure increases and to gradually shorten the extentof the flow passage 50 as supply line fluid pressure decreases withouthaving to worry about trying to sequentially close the baffles of thepressure-reducing passage 50.

In alternate embodiments, it should be understood that alternateportions of the emitter body 20 may be moved to compensate for increasesin fluid line pressure, either in conjunction with or in lieu of thosediscussed above. For example, in one alternate form, the emitter body 20may be designed so that additional sections of the baffle walls 51, 52may be moved to compensate for pressure increases in the supply line 70.More particularly and as illustrated in FIGS. 2A-D, both the innerbaffle wall and outer baffle wall may be designed to move and lengthenthe flow path to compensate for increases in supply line fluid pressure.For convenience, items which are similar to those discussed above withrespect to emitter 10 in FIGS. 1A-F will be identified using the sametwo digit reference numeral in combination with the prefix “1” merely todistinguish one embodiment from the other. Thus, the emitter bodyidentified in FIGS. 2A-D is identified using the reference numeral 120since it is similar to emitter body 20 discussed above. Similarly, theinlet, outlet and pressure-reducing flow channel are identified usingreference numerals 130, 140 and 150 since they are similar to theabove-mentioned inlet, outlet and flow channel 30, 40 and 50.

While the emitter body 120 of FIGS. 2A-F defines both apressure-reducing flow channel 150 and a two part pressure compensatingmechanism 160 having an elastomeric portion 161 and moveable baffleportion 162 like the embodiment of FIGS. 1A-H, the moveable baffleportion 163 in FIGS. 2A-F is made up of portions of the inner and outerbaffle walls 151, 152 rather than just the inner baffle wall 151. Moreparticularly, the inner and outer baffle walls 151, 152 move tocompensate for fluid pressure increases and decreases in the supply linefluid. In the form illustrated, the central or inner baffle wall 151tapers at its distal end into a tapered tongue-type structure orprojection 163 to form a first moveable structure and the outer bafflewall 152 defines a mating fork or groove-type structure 164 thatcorresponds in shape to the tongue-type structure 163 to form a secondmoveable structure.

As best illustrated in FIG. 2F, the tongue and fork or groove structures163, 164 cooperate with one another so that when the floor 161 of theflow channel 150 rises in response to increases in supply line pressure,the tapered structures 163, 164 both rise toward the inner surface ofthe tube 170, thereby reducing the amount of fluid that can flow overthe upper surfaces of the tapered structures 163, 164 and effectivelylengthening the flow channel 150 and reducing the cross-section of theflow channel 150 to compensate for the increase in supply line fluidpressure. Similarly, when the floor 161 of flow channel 150 falls inresponse to a decrease in supply line pressure, the tapered structures163, 164 both move away from the inner surface of the tube 170, therebyincreasing the amount of fluid that can flow over the top of the uppersurfaces of the tapered structures 163, 164 and effectively shorteningthe length of the flow channel 150 and increasing the cross-section ofthe flow channel 150 to compensate for the decrease in supply line fluidpressure as illustrated in FIG. 2E.

In the form illustrated, the upper surfaces of the tapered structures163, 164 never fully seal against the inner wall of the tube 170 whenmoved to their high pressure position, however, in alternate forms, thetapered structures 163, 164 could be designed such that this occurs ifdesired. Similarly, the embodiment of FIGS. 1A-H could be designed sothat the upper surface of the tapered baffle section 62 does not sealcompletely against the inner surface of the tube 70, if desired.

It should be understood that in alternate embodiments, the first andsecond moveable structures 163, 164 of the inner and outer baffle walls51, 52 could be swapped so that the inner baffle wall 51 terminated in agroove-type structure and the outer baffle wall 52 defined a tongue-typestructure, or in yet other forms, both could define other structuresmeant to correspond with one another or mesh with one another to achievethe same effect of lengthening and shortening the flow channel 50 inresponse to increases and decreases in supply line fluid pressure,respectively, and if desired, reducing and increasing the cross-sectionof the flow channel 150 in response to increases and decreases in supplyline fluid pressure, respectively. For example, in alternate forms, boththe inner and outer baffle walls 51, 52 could define structures thatcorrespond in shape with one another including but not limited tointermeshing U- or V-shaped structures that lengthen the flow channel150 and reduce the cross-section of the flow channel 150 in response toincreases in fluid pressure and that shorten the flow channel 150 andincrease the cross-section of the flow channel 150 in response todecreases in fluid pressure.

Thus, with this configuration, an irrigation drip emitter 110 isprovided for attachment to only a portion of an inner circumference ofan inner surface of an irrigation drip line tube 170 having anelastomeric emitter body 120 integrally defining an inlet 130 forreceiving pressurized fluid from a fluid supply source, an outlet area140 for discharging the fluid from the body 120, a pressure reducingflow path 150 extending between the inlet 130 and the outlet area 140for reducing the pressure and flow of fluid received at the inlet 130and discharged through the outlet area 140, and a pressure compensatingportion 160 for automatically adjusting the pressure and fluid flowreducing effect of the flow channel 150 in response to a change inpressure of the fluid supply source 170, wherein the pressure reducingflow channel 150 includes an inner baffle wall 151 and an outer bafflewall 152 that extends about the inner baffle wall 151 in a generallyU-shaped manner. At least some of the upper surfaces of the baffle walls151, 152 having a first radius of curvature that corresponds with asecond radius of curvature of an inner wall of the irrigation drip linetube 170 and the inner baffle wall 151 defines a first tapered bafflestructure 163 and the outer baffle wall 152 defines a second taperedbaffle structure 164 positioned proximate the first baffle structure163, with the first and second tapered baffle structures 163, 164cooperating to form part of the pressure reducing flow channel 150 andthe first and second tapered baffle structures 163, 164 tapering inheight toward one another and being variably moveable between a firstposition wherein the upper surfaces of the first and second taperedbaffle structures 163, 164 are not level with the upper surfaces of thebaffle walls with the first radius of curvature so that fluid can flowover the first and second tapered baffle structures 163, 164 and asecond position wherein the upper surfaces of the tapered bafflestructures 163, 164 move toward and/or are at the same level as theother upper surfaces of the baffle walls with the first radius ofcurvature and fluid is restricted from flowing over at least a portionof the first and second tapered baffle structures 163, 164 and thecross-section of the flow channel 150 proximate the first and secondbaffle structures 163, 164 is reduced and the length or extent of theflow channel 150 is lengthened.

In yet other embodiments, the two part pressure compensating mechanismmay use other types of moveable walls in combination with a deflectingmember to compensate for changes in fluid pressure. For example, in thealternate embodiment illustrated in FIGS. 3A-G, the emitter body isdesigned with a plurality of fluid inlet openings with sleeves orannular walls extending therefrom, which can move in response toincreases and decreases in supply line fluid pressure. For convenience,items which are similar to those discussed above with respect to emitter10 in FIGS. 1A-F and emitter 110 in FIGS. 2A-F will be identified usingthe same two digit reference numeral in combination with the prefix “2”merely to distinguish this embodiment from the others. Thus, the emitterbody identified in FIGS. 3A-F is identified using the reference numeral220 since it is similar to emitter bodies 20 and 120, and defines aninlet 230, outlet 240 and pressure-reducing flow channel 250, which aresimilar to those discussed above (i.e., inlet 30, 130, outlet 40, 140,and pressure-reducing flow channel 50, 150). In addition, the uppersurfaces of the peripheral wall of emitter body 220, inner and outerbaffle walls 251, 252, and nubs 241 all have a first common radius ofcurvature that corresponds with a second radius of curvature of an innerwall of the irrigation drip line tube 270.

Unlike the embodiments discussed above, however, the inlet 230 ofemitter body 220 comprises a plurality of inlet openings 232, 233, 234,235, 236 and 237. In the form illustrated, the inlet openings 232-237vary in height, with the initial inlet opening 232 being flush to thefloor 261 of the pressure-reducing flow channel 250 and the remaininginlet openings 233-237 having annular walls, such as sleeves or bosses233 a, 234 a, 235 a, 236 a and 237 a, respectively, that have terminalends that progressively extend further into the pressure reducing flowchannel 250 with the terminal end of each boss moving variably from anopen position wherein the terminal end of the boss is not generallylevel or flush with the first common radius of curvature of the uppersurfaces of the baffle walls 251, 252 so that fluid can flow through theboss and into the flow channel 250, and a closed position wherein theterminal end of the boss is generally level or flush with the firstcommon radius of curvature of the upper surfaces of the baffle walls251, 252 so that fluid is prevented from flowing through the boss andinto the flow channel 250.

In a preferred form, the upper surfaces of the terminal end of thebosses 233 a-237 a have a radius of curvature that is the same as thefirst common radius of curvature of the upper surfaces of baffle walls251, 252 which corresponds with the second radius of curvature of theinner wall of the irrigation drip line tube 270 so that the bosses 233a-237 a can close flush against the inner wall of tube 270 and preventfluid from flowing through the boss and into the flow channel 250 whenraised into engagement with the inner wall of tube 270. In addition, theheight of the bosses 233 a-237 a are varied so that the inlets 233-237close sequentially starting with the inlet furthest from the initialinlet opening 232 (i.e., which in the illustrated example is inlet 237)and then moving to the inlet that is the next furthest (i.e., 236), thenthe next furthest (i.e., 235) and so on. By closing the inlets 233-237in this order (i.e., starting with the inlet furthest downstream andmoving upstream), the emitter body 220 actually lengthens thepressure-reducing passage 250 with each sequential closing for all fluidflowing therethrough which allows the emitter to compensate forincreases in the supply line fluid pressure. Conversely, as supply linefluid pressure decreases, the emitter body opens the inlets 233-237beginning with the inlet furthest upstream and moving downstream, whichallows the emitter to shorten the pressure-reducing passage 250 for someof the fluid flowing through the emitter to compensate for the reductionin supply line fluid pressure.

In the form illustrated, it is contemplated that each of inlet openings233-237 will close during normal operation of the emitter 210, or thatthe emitter body 220 will be designed such that inlet openings 233-237will normally close at some point during the operation of the emitterdue to expected increases in supply line fluid pressure (i.e., thatenough pressure is expected to be reached that will cause inlets 233-237to close at some point or another). However, it should be understoodthat in alternate embodiments, the emitter body 220 may be designed toonly shut one or more of the inlets 233-237 during normal or expectedsupply line fluid pressure conditions and only having the remaininginlets 233-237 close under extraordinary conditions (e.g., when supplyline fluid pressures are reached that are much greater than normal orexpected pressures). This can either be done by altering the size of theemitter body 220 or any of its features (e.g., inlet opening, floorthickness, baffle wall size, flow path cross-section, etc.) or by usingdifferent materials for body 220 (e.g., materials with differentDurometer values, different compositions that make the body 220 harderor less flexible, etc.). Conversely, the emitter body 220 may be made ofmaterials that allow for inlets 233-237 to close more rapidly if desired(e.g., by altering body features and/or selecting different materials asdiscussed above). In this way, the emitter 10 can be customized forspecific applications.

Thus, with this configuration, an irrigation drip emitter 210 isprovided for attachment to only a portion of an inner circumference ofan inner surface of an irrigation drip line tube 270 having anelastomeric emitter body 220 integrally defining an inlet 230 forreceiving pressurized fluid from a fluid supply source, an outlet area240 for discharging the fluid from the body 220, a pressure reducingflow path 250 extending between the inlet 230 and the outlet area 240for reducing the pressure and flow of fluid received at the inlet 230and discharged through the outlet area 240, and a pressure compensatingportion 260 for automatically adjusting the pressure and fluid flowreducing effect of the flow channel 250 in response to a change inpressure of the fluid supply source 270, wherein the pressure reducingflow channel 250 includes an inner baffle wall 251 and an outer bafflewall 252 that extends about the inner baffle wall 251 in a generallyU-shaped manner. With at least some upper surfaces of the baffle walls251, 252 having a first common radius of curvature that corresponds witha second radius of curvature of an inner wall of the irrigation dripline tube 270, and the inlet 230 includes a plurality of inlet passages232-237 with each passage 232-237 extending from a surface of the bodyexposed to the pressurized fluid to the pressure reducing flow channel250, with at least some of the inlet passages 233-237 extending throughbosses each having a terminal end progressively extending further intothe pressure reducing flow channel 250, the terminal end of each bossbeing moveable variably from an open position wherein the terminal endof the boss is not level with the upper surfaces of the baffle wallshaving the first radius of curvature so that fluid can flow through theboss and into the flow channel 250 and a closed position wherein theterminal end of the boss is generally level with the upper surfaces ofthe baffle walls having the first radius of curvature so that fluid isprevented from flowing through the boss and into the flow channel 250.

It should be understood that in alternate embodiments, the sleeves orbosses 233 a-237 a may take on other shapes and sizes as may be desiredfor specific applications. For example, in some applications, inletswith rectangular cross sections may be desired over the round inletsdepicted in FIGS. 3A-G. In yet other forms, inlet passages that servesome form of pressure reduction, such as passages that define tortuouspaths, may be desired. In still other embodiments, fewer or more inletopenings or bosses may be provided than those shown in FIGS. 3A-G ifdesired. For example, in FIG. 4, an alternate drip emitter and drip lineis illustrated having an inlet made-up of a plurality of inlet openings.In keeping with the above practice, features that are common to thosediscussed above will use the same two-digit reference numeral, buthaving the prefix “3” merely to distinguish one embodiment from another.

In the form illustrated in FIG. 4, the plurality of inlets are shapedlike elongated openings, such as slits or slots 330, which not onlyallow fluid to flow through the inlet of the emitter 310, but also helpfilter or deflect particulates such as grit away from the emitter 310 tohelp ensure the fluid flowing through the emitter 310 is free of suchparticulates so that the particulates do not interfere with theoperation of the emitter 310. The plurality of openings 330 havelongitudinal axes that parallel the longitudinal axis of the emitter310, however, in alternate forms, it should be understood that theplurality of openings may take on a variety of different shapes andsizes and may be oriented in different ways so as not to havelongitudinal axes parallel to the longitudinal axis of the emitter 310(if even having longitudinal axes).

In alternate forms, it should be understood that the inlet or inlets ofthe emitter may be placed in certain positions to help determine how theemitter will operate. For example, in some forms, an inlet opening maybe positioned further upstream to effectively shorten the length of thepressure-reducing flow channel and create an emitter that has a higherfluid flow rate (e.g., four gallons per hour or 4 GPH). In another form,the inlet opening may be positioned further downstream to effectivelylengthen the pressure-reducing flow channel and create an emitter thathas a lower flow rate (e.g., 1 GPH). In still another form, the inletopening may be positioned somewhere in-between the above mentionedlocations to create an emitter with an intermediate pressure-reducingflow channel length that has a flow rate somewhere in-between the otherflow rates (e.g., 2 GPH). The changing of this inlet location could beaccomplished by having a readily adjustable mold (e.g., one where thelocation of the inlet opening can be slid or moved between the desiredlocations) or, alternatively, separate molds could be made for eachembodiment (i.e., one for the low flow rate emitter, another for theintermediate flow rate emitter, and another for the high flow rateemitter).

The same may be true for outlet openings. For example, whenmanufacturing the drip line, the location of the outlet opening may bealtered to affect how the emitter will operate. The outlet opening couldbe located further upstream to effectively shorten the pressure-reducingflow channel and create an emitter with a higher flow rate (e.g., 4GPH). In another form, the outlet opening may be located furtherdownstream to effectively lengthen the pressure-reducing flow channeland create an emitter with a lower flow rate (e.g., 1 GPH). In anotherform, the outlet opening may be positioned somewhere between the abovementioned locations to effectively create an emitter with anintermediate pressure-reducing flow channel length that operates with afluid flow rate somewhere between the above-mentioned flow rates (e.g.,2 GPH). The outlet opening may be formed in the drip line tubing beforeor after the emitter is bonded to the inner surface of the tubing,however, in a preferred form, the opening will be formed after theemitter is bonded to the inner surface of the tubing. The opening istypically formed via a die, press, awl or the like. Thus, adjustments tothe location of where the outlet opening can be made by adjusting wherethis puncture occurs in the tubing.

In addition, in some forms, color may be added to the individualemitters and/or the drip line and methods of manufacturing same todistinguish these products or product lines from one another or tosignify something relating to the items intended use or application. Forexample, one color may be used to identify an emitter or dip line thatdrips at a rate of one gallon per hour (1 GPH), another color may beused to identify an emitter or drip line that drips at a rate of twogallons per hour (2 GPH), another color may be used to identify anemitter or drip line that drips at four gallons per hour (4 GPH). In oneform, emitters of different flow rates are distinguished by color sothat workers can more easily determine which emitters are to be insertedinto extruded tubing during assembly in order to obtain a drip line withcommon emitter drip rates. In another form, the extruded tubing may bemade in a specific color or have a marking of a specific color todesignate the flow rate of the drip emitters located therein in order tohelp workers and/or end users distinguish drip lines of different driprates. In still other forms, both the emitters and the tubing mayinclude color to specify the drip rate or intended application. In otherforms, colors may be used to signify the source of fluid to be used withthe emitter or drip line or the particular application for which theemitter or drip line is to be used. For example, the color purple isoften used to indicate that reclaimed or recycled water is being used.Thus, the emitter or drip line could be marked with this color toindicate that the emitter or drip line is intended for these types ofapplications or to indicate the type of fluid that is supposed to travelthrough these types of emitters/drip lines. If desired, any of theembodiments and methods disclosed herein could include the addition ofcolor for such purposes.

Turning back to the embodiment of FIG. 4, it should be appreciated thatin this form, the emitter 310 includes a baffle design having teethextending from the sides of the emitter body 320 toward one another toform the tortuous flow passage 350 without a central baffle portion. Theheight of each tooth is higher at the sides of the emitter body 320 thanat the distal end of each tooth and, as fluid pressure increases, thefloor 361 of flow channel 350 moves up toward the inner surface of thetube 370 causing the portions of the teeth closest to the sides of theemitter body 320 to close against (e.g., touch, engage, etc.) the innersurface of the tube 370 first, before gradually closing more and more ofeach tooth against the inner surface of tube 370 simultaneously untilthe floor 361 cannot move any further. Thus, rather than closing thebaffle teeth consecutively or sequentially against the inner surface oftube 370 to lengthen the pressure-reducing flow passage 350 andcompensate for the increase in pressure, this configuration allows eachtooth to gradually close against the inner surface of tube 370simultaneously in response to increases in line pressure therebylengthening the pressure-reducing flow passage 350 and reducing thecross-section of the pressure-reducing flow channel 350 to form apressure compensating mechanism 360 that compensates for increases anddecreases in line pressure. For convenience, only a portion of tube 370is illustrated in FIG. 4 so that a portion of the emitter body 320remains visible, however, it should be understood that the tube 370would extend over the entire emitter body 320 and that the emitter body320 would be bonded to the inner surface of the tube in a manner similarto that discussed above.

In the form illustrated, fluid flowing through the drip line 370 entersthe emitter 310 via inlet openings 330, travels through the tortuouspassage 350 and then exits the emitter 310 via outlet opening 371. Thepressure compensating mechanism 360 reduces the cross-section of theflow channel 350 by raising the floor 361 of flow channel 350 andpressing more of the upper surfaces of the baffle teeth into engagementwith the inside surface of the tubing 370 as fluid pressure increases,and increases the cross-section of the flow channel 350 by allowing thefloor 361 of flow channel 350 to move away from the inner surface oftubing 370 as fluid pressure decreases. This configuration also providesa large central flow path down the middle of the pressure-reducing flowchannel 350 which allows for easier processing of grit or otherparticulates, particularly at start-up and shutdown of fluid flow due tothe low pressures associated with same and due to the fact the portionof the flow channel 350 with the largest cross-sectional area willalways remain in the middle of the emitter 310 and, specifically, at thelongitudinal axis of the flow channel 350.

FIGS. 5A-B are perspective views of an alternate drip emitter and dripline embodying features of the present invention wherein thepressure-reducing flow channel is made-up of baffles with flexible teeththat move in response to fluid flow through the emitter body. In keepingwith above practices, items that are common to those discussed abovewill use the same two digit reference numeral but with the addition ofthe prefix “4” to distinguish one embodiment from another. In the formillustrated, only a portion of the tube 470 is illustrated in FIG. 5A sothat the details of emitter body 420 may be seen, however, it should beunderstood that the entire emitter body 420 would be inserted within thetube 470 and connected to an inner surface of tube 470.

The emitter 410 includes a plurality of flexible baffle walls extendingfrom opposite sides of the emitter body 420 toward one another and in astaggered arrangement so one wall is not directly opposite a wall on theother side of the emitter body 420. In the form illustrated, the bafflewalls form flexible teeth that are much narrower than those discussedabove and form generally rectangular walls connected at their base tothe floor 461 of the pressure-reducing flow channel 450 and on one sideto the side of the emitter body 420. Thus, when fluid flows through thesupply line 470, at least a portion of the fluid flows through the inletopening 430, through the tortuous passage 450 defined by the bafflewalls 452, to the outlet 440 and through outlet opening 471. As thesupply line fluid pressure increases, the floor of the flow channel 461moves toward the inner surface of tube 470 driving the tops of thebaffle walls into engagement with the inner surface of the supply linetubing 470 and, thereby, restricting or reducing the cross-sectionalarea of the flow channel 450 and/or increasing the length of the flowchannel 450 in response to the increase in pressure in order tocompensate for the supply line fluid pressure increase. As the fluidpressure in the supply line continues to increase, the baffle walls 452closest to inlet 430 flex or bend over in the direction of the fluidflow. This occurs because the pressure of the fluid is always greaterthan the pressure of the floor 461 raising the baffle walls 452 intoengagement with the inner surface of the tube 470. As fluid pressureincreases further within tube 470, more and more of the flexible bafflewalls 452 will flex or bend in the direction of the fluid flow which canalso help the emitter process obstructions such as grit or otherparticulates by allowing the baffle walls to bend so that theobstructions can be carried through the flow channel and out of theemitter 410. Conversely, when fluid pressure decreases in the supplyline 470, the baffle walls cease bending and return to their normalpositions (e.g., as illustrated in FIG. 5A) and the floor 461 lowers,allowing the walls 452 to move away from the inner surface of tube 470and thereby increasing the cross-sectional area of the flow path 450and/or reducing the length of the flow channel 450 to account for thedecrease in fluid pressure. In this way, emitter 410 is equipped with apressure compensating mechanism 460 like some of the other embodimentsdiscussed herein.

Although the embodiment illustrated shows circular inlets and outletopenings 430 and 471, it should be understood that in alternateembodiments, these inlet and outlet openings may take on a variety ofdifferent shapes and sizes. In addition, in alternate forms, the emitterbody 420 may be designed with larger pools or baths located at the inlet430 and outlet 440 (like the embodiment of FIGS. 1A-H), instead ofdirectly transitioning to the tortuous flow passage 450 as illustratedin FIGS. 5A-B. Furthermore, the flexible baffle walls 452 disclosed inthis embodiment could easily be used in any of the other embodimentsdisclosed herein, just like any of the features of the variousembodiments discussed herein could be mixed and matched together to formanother embodiment regardless of which embodiment the specific featureis currently illustrated in. Thus, in one form, the flexible teeth 452may be used in an embodiment more like that shown in FIGS. 1A-H (e.g.,with a U-shaped tortuous passage). In still other forms, the flexibleteeth 452 may be attached to the emitter body 420 in such a way as to bepredisposed to flex or bend in a preferred direction. For example,rather than having the flexible teeth 452 bend in the same direction thefluid flows through the emitter 410, the teeth 452 could be predisposedwith an angle causing the teeth 452 to bend in a direction opposite thefluid flow in order to cause more turbulence and interference with thefluid flowing through the emitter 410. As mentioned above, however, in apreferred form of the embodiment of FIGS. 5A-B, the baffle walls 452will bend in the same direction as the fluid flow.

Yet another embodiment of an alternate drip emitter and drip line inaccordance with the invention is illustrated in FIGS. 6A-D. As with theother embodiments discussed herein, this embodiment will use the sametwo digit reference numeral to refer to items similar to those discussedabove, but will include the prefix “5” to distinguish one embodimentfrom the others. Thus, in the form illustrated in FIGS. 6A-D, theemitter 510 includes an emitter body 520 having an inlet 530, outlet 540and tortuous flow path 550 extending therebetween; however, unlike theprevious embodiments discussed herein, the baffle walls 552 include atleast one hollow portion which fills with fluid as the supply line fluidpressure increases in order to reduce the cross-sectional area and/orincrease the length of the flow channel 550 to compensate for anincrease in fluid pressure.

More particularly, in the form illustrated in FIGS. 6A-D, the teeth 552of the baffle walls are hollowed-out or define an opening or void 554 inorder to allow supply line fluid to fill the void 554 of the hollowteeth 552 (or the space 554 defined by each hollow tooth) and, as supplyline fluid pressure increases, to swell or enlarge the size of eachtooth 552 by filling this void with pressurized fluid and therebycausing the size of the teeth to grow/expand and reduce thecross-sectional area of the flow channel 550 to compensate for theincrease in the fluid pressure. A view of the bottom of emitter body 520(which is the side of the emitter facing the fluid flowing throughsupply line 570) is illustrated in FIG. 6D showing the void 554 andillustrating how some of the supply line fluid is able to flow along thebottom surface of the emitter body 520, fill the voids 554 of the hollowteeth, enter the inlet 530 of the emitter and/or continue flowing downthe supply line 570.

As fluid pressure increases, the floor of the emitter 561 will also moveupwards and, thus, the upper surfaces of the baffle walls 552 willgradually engage more and more of the inner surface of tube 570 therebyincreasing the length of the tortuous passage 550 that the fluid mustflow through in order to compensate for the increase in fluid pressure.Conversely, when fluid pressure decreases, the floor 561 will drop,gradually disengaging the baffle walls 552 from the inner surface of thetube 570 and the teeth 552 will shrink or reduce in size to effectivelyincrease the cross-sectional area of the flow path 550 and reduce thelength of the tortuous passage that the fluid must flow through tocompensate for the reduction in fluid pressure. Thus, like the previousembodiments discussed herein, the emitter 510 is equipped with both apressure-reducing flow path 550 and a pressure compensating mechanism560 for ensuring that each emitter operates uniformly and as desired.

In FIG. 6A, the supply line fluid pressure is low and, thus, the teethof baffle walls 552 are not enlarged and the upper surfaces of thebaffle walls are not fully engaged with the inner surface of the supplyline tube 570. This reduces the length of the flow channel 550 that thefluid must flow through and allows for the flow channel 550 to have amaximum cross-sectional area. In FIG. 6B, the supply line fluid pressurehas increased some to a generally intermediate level of pressure suchthat the teeth of baffle walls 552 have enlarged a bit and the uppersurfaces of the baffle walls nearest the side of emitter body 520 beginto engage the inner surface of supply line tube 570. This increases thelength of the flow channel 550 that the fluid must flow through andreduces the cross-sectional area of the flow channel 550 to account foror compensate for the increase in fluid pressure. In FIG. 6C, the supplyline fluid pressure has increased further to a high level of pressuresuch that the teeth of the baffle walls 552 have grown or enlarged totheir maximum size (or close to their maximum size) and the uppersurfaces of the baffles fully engage the inner surface of the supplyline tube 570. This further increases the length of the flow channel 550that the fluid must flow through (thereby maximizing the amount ofpressure-reduction taking place via flow channel 550) and reduces thecross-sectional area of the flow channel 550 to its smallestcross-sectional area to compensate for the increase in fluid pressure.In addition, the baffle teeth 552 in FIG. 6C are shown tipping orbending in the direction of the fluid flow (similar to that shown withrespect to the embodiment of FIGS. 5A-B). Thus, with this configuration,the pressure-reducing flow channel has a first cross-sectional area atlower fluid pressures, a second cross-sectional area, smaller than thefirst, at higher fluid pressures to compensate for the increase in fluidpressure so that the emitter and drip line trickle fluid at a generallyconstant or desired rate, and a plurality of gradually decreasingcross-sectional areas as the fluid pressure increases from the pressurethat exists at the first cross-sectional area to the pressure at thesecond cross-sectional area.

FIGS. 6B-C are perspective views of a portion of the flow channel ofFIG. 6A illustrating the hollow teeth of the baffle partially enlargedand fully enlarged, respectively, in response to increasing fluidpressure showing how the cross-sectional area of the pressure-reducingflow channel in FIG. 6B has a smaller cross-sectional area than thatillustrated in FIG. 6A due to an increase in fluid pressure and showinghow the cross-sectional area of the pressure-reducing flow channel ofFIG. 6C is even smaller than that illustrated in FIG. 6B due to afurther increase in fluid pressure.

Another emitter embodying features of the present invention is shown inFIGS. 7A-I. In keeping with the above practices, this embodiment willuse the same latter two-digit reference numerals to describe items thatare similar to those discussed above, but will include the prefix “6”merely to distinguish one embodiment from another (e.g., emitter bodywill be referenced as 620 indicating it is similar to prior emitterbodies 520, 420, 320, 220, 120 and 20).

In this embodiment, the emitter 620 is made of an elastomeric materialand defines a single pressure reducing flow channel or passage 650 laidout in a generally straight pattern like those illustrated in FIGS. 4-6Dabove, rather than a curved or U-shaped pattern like those illustratedin FIGS. 1A-3G. The flow channel 650 has a plurality of teeth extendingfrom outer baffle walls 552 that move in response to changes in fluidpressure in order to provide a pressure compensating emitter. In thisparticular embodiment, however, the unitary emitter body 620 definesfirst and second outer baffle walls 652 a, 652 c that are interconnectedvia hinge or joint 652 e. The baffles of first wall 652 a extend intothe flow path via teeth 652 b and the baffles of wall 652 c extend outinto the flow path via teeth 652 d. When fluid pressure increases, thewalls 652 a, 652 c and their respective teeth 652 b, 652 d are movedfrom a first or static position wherein the walls and teeth are spacedapart from one another to a second, higher or high pressure positionwherein the walls and teeth are squeezed closer together to one anotherthereby reducing the cross-section of the fluid passage 650 andrestricting the amount of fluid that is allowed to flow through emitter620 and reducing the flow rate of same. In this way, the entire fluidpassage 650 is capable of serving as the pressure compensating member660.

More particularly and as best shown in FIGS. 7B, 7C-E, 7G and 71, theunitary emitter body 620 defines an inlet 630, outlet 640 and havingfirst wall 652 a and second wall 652 c between the inlet 630 and theoutlet 640. The first and second walls 652 a, 652 c define a pressurereduction or reducing flow channel 650 and having interconnecting memberor interconnection 650 e between one another. In this way, emitter 620operates similar to emitter 520 (FIGS. 6A-D) in that increases in fluidpressure result in lateral or sideways movement or growth of teeth 652b, 652 d to reduce the size of the flow path 650 and, in particular, theeffective cross-section of the flow passage 650.

In the form illustrated in FIGS. 7E and 71, the side walls 652 a, 652 cand interconnecting member 652 e form an arcuate cross-sectional shape(e.g., a generally U-shape) extending down from the top of emitter 620and running along the longitudinal axis of the emitter 620. In additionand as best illustrated in FIGS. 7D and 7E, the flow channel or passage650 further increases in height from the inlet side or end 630 of theemitter 620 to an intermediate point of the emitter 620, but thendecreases in height from the intermediate point of the emitter 620 tothe outlet end 640 of the emitter 620. More particularly, the walls 652a, 652 c increase in height from the inlet end of the emitter 630 to thegeneral middle or center of the emitter 620 and then decrease in heightfrom the middle/center of emitter 620 to the outlet portion 640 ofemitter 620. Thus, the pressure reducing channel 650 has a varyingcross-sectional area along its longitudinal axis and the maximumcross-sectional area of the flow channel 650 is in the intermediateportion of the flow channel 650.

In a preferred form, the alternating series of baffles 652 b, 652 dextending from first and second walls 652 a, 652 c vary in length orheight in a manner corresponding with the varying length or height ofwalls 652 a, 652 c giving the first and second walls a cross-sectionthat appears as an oval at certain planes as illustrated in FIG. 7D.This configuration means that the intermediate portion 650 f of the flowchannel 650 will have the maximum length or height for baffles 652 b,652 d, and that this portion of the flow channel 650 will be affectedfirst in relation to fluid pressure increases due to it offering moresurface area than other portions of the flow channel 650. Thus, the flowchannel 650 will be squeezed or pinched in the intermediate area 650 fof the emitter first, before elsewhere along the flow channel (e.g.,before the portions at or near the input and output ends 630, 640).

As best illustrated in FIGS. 7C and 7D, the baffles 652 b, 652 d arepreferably tooth shaped, having the edges of the baffles 652 b for thefirst wall 652 a overlap with the edges of baffles 652 d for the secondwall 652 c. In the form illustrated, the overlap is approximatelytwenty-thousandths of an inch (0.020″) with the teeth 652 b, 652 dvarying in length or height from thirty-thousandths of an inch (0.030″)to one hundred-thousandths of an inch (0.100″) and having a maximum flowgap when the first and second walls 652 a, 652 c are in their static ornon-moved position of thirty-thousandths of an inch (0.030″)(the bridgegap between first and second walls 652 a, 652 c being approximatelyfifty-thousandths of an inch (0.050″). It should be understood, however,that in alternate embodiments these dimensions may be changed andinstead of having an overlap between teeth 652 b, 652 d, a gap may bemaintained to assist with flushing the emitter 650 of obstructions suchas grit (as discussed above).

Another difference with respect to emitter 620 of FIGS. 7A-I and priorembodiments is that the emitter 620 defines an outlet bath 640 that hasprojections such as walls or posts/stanchions 641 to prevent the outletpool 640 from collapsing under increases in fluid pressure. In this way,these structures 641 are similar to the nubs discussed above (e.g., 41,141 and 241), however, they connect to the outer wall of the emitter620, the wall that defines the bath 640, rather than rising up from thesurface of the floor of the outlet 640.

As with earlier embodiments, the emitter 620 has a top surface that iscapable of being attached to the inside surface of a conduit (not show)at predetermined intervals thereof in order to form a drip line usingsaid emitter. Unlike prior embodiments which used guide ribs (e.g.,25-29), the emitter body 620 uses guide recesses or slots 621 and 624for aligning the emitter 620 and inserting same into the conduit duringconstructions, preferably as the conduit is extruded. The inlet 630 alsopreferably has a recessed opening or inlet, such as channel 631 whichhelps to prevent large obstructions from entering into the emitter 620during operation within a fluid-filled drip line.

Turning now to FIGS. 8A-G, in which there is illustrated yet anotheremitter embodying features of the present invention, this emitterdefines a series of rows of baffles transverse to the longitudinal axisof the emitter and extending into the pressure reduction flow path, witha portion of the baffles varying in height to create a structure thatcompensates for pressure. In keeping with the above, items that aresimilar to those discussed in earlier embodiments will be referencedusing the same last two-digit identifier, but using the prefix “7” todistinguish one embodiment from others. Thus, in the form illustrated,the emitter body is referenced by reference numeral 720.

In the form illustrated in FIGS. 8A-G, the unitary emitter body 720 ismade of an elastomeric material and defines a single pressure reducingflow channel or passage 750 laid out in a generally serpentine pattern.The body 720 has a longitudinal axis and defines an inlet 730 and outlet740 in addition to the pressure reduction flow path 750 which connectsboth the inlet 730 and outlet 740. The body 720 has a series of rows ofbaffles 752 g-m, extending transverse to the longitudinal axis of theemitter 720 and into the pressure reduction flow path 750. A firstseries of baffles, 752 g, 752 h and 752 i have constant height, whereas,a second series of baffles, 752 j, 752 k, 752 l and 752 m vary inheight. The baffles having a varying height, 752 j-752 m, have a staticor normal position and a pressurized elevated position (or elevatedpressure position).

In the embodiment depicted, the baffles are shaped in the form of teethpositioned about a wall wherein each varying height baffle tooth has abase 752 n and a distal or terminal end 752 o with the varying heightbeing at a maximum height at the base 752 n and at a minimum height atthe distal or terminal end 752 o. The baffle teeth are staggered orpositioned to alternate with one another so that the teeth alignopposite gaps between teeth members on the opposite wall defining thefluid flow passage 750.

In FIGS. 8A-G, at least two rows of the series of baffles (e.g., 752 k,752 l) include varying height teeth members. An additional two rows ofthe series of baffles (e.g., 752 j, 752 m) include varying height teethmembers on one side of the baffle. Baffle row 752 j includes teeth ofcontinuous height extending from one side of the row (e.g., the sidefacing the inlet 730) and teeth of varying height on the opposite sideof the row (e.g., the side facing outlet 740). Baffle rows 752 h and 752i having continuous height (including all teeth). Baffle rows 752 g and752 m have teeth extending from only one side of their respective row,with the baffle row 752 g being of continuous height and baffle row 752m being of varying height. Thus, with this configuration, the baffleswith varying height 752 j-m server as the pressure compensating member760 for emitter 720.

Thus, when a plurality of emitters 720 are installed in a conduit toform a drip line, fluid will flow through the conduit, into the inlet ofthe drip emitter 720 and through pressure reducing flow passage 750. Asfluid pressure increases in the conduit, the passage floor of passage750 will push up into the flow passage 750 in at least the areas wherebaffles of varying height are provided (e.g., compensation portion 760)due to the spacing that exists and allows for baffle movement. This willcause the baffle teeth to move to their elevated pressure position,preferably forcing their upper surfaces to engage the inside surface ofthe conduit (or approaching such engagement), thereby, reducing thecross-section of the flow passage 750 in this area and restricting theamount of fluid that can flow through this region in order to compensatefor the fluid pressure increase. In this way, the emitter operatessimilar to the emitter embodiments discussed above with respect to FIGS.1A-I and 2A-F.

Although the embodiment depicted in FIGS. 8A-G shows specific series ofbaffles having continuous height and varying height, it should beunderstood that in alternate embodiments, more or less of the baffles752 g-m may have varying heights. In fact, in some forms, all of thebaffles may be provided in constant height (for example, in situationswhere no pressure compensation feature is required or desired for theemitter). Alternatively, in other embodiments, all of the baffles mayhave some form of varying height component.

In FIGS. 8A-G, the emitter 720 preferably includes a guide recess, suchas channel 721, which serves the dual role of helping position or alignthe emitter 720 for insertion into the conduit and helps recess theinlet 730 of emitter 720 into a recessed opening 731 which helps blocklarger obstructions from entering into the emitter 720 or at leastblocking all flow of fluid into the inlet 730.

The emitter body 720 further defines an outlet bath 740 and the pressurereduction flow path 750 includes an outlet end at the outlet bath. In apreferred form, the unitary emitter body 720 will include at least oneprojection 741 in the outlet bath 740 to prevent the outlet bath fromcollapsing under increased fluid pressure. In the form illustrated, aplurality of projections or nubs 741 extend up from the floor of theoutlet 740 to prevent collapse of the bath 740. Additional rectangularnotches or voids are illustrated in FIG. 8E which show how the emitterbody 720 may be designed to use less elastomeric material, which notonly will have a material cost savings, but also will reduce the amountof time it takes to manufacture the emitter 720 and may potentiallyimprove the operation of the pressure compensating portion 760 of theemitter 720 due to the fact thinner portions of elastomeric materialwill be more responsive to pressure increases than larger portions ofelastomeric material.

Turning now to FIGS. 9A-B, there is illustrated yet another emitterembodying features of the present invention wherein a unitary emitterbody defines a series of rows of baffles transverse to the longitudinalaxis of the emitter and extending into the pressure reduction flow path,and a plurality of outlet baths with at least a portion of outlet bathsbeing moveable between first and second positions, the second positionbeing more constrictive for fluid flow than the first position. Inkeeping with the above, portions of this embodiment that are similar tothose discussed above will use the same last two-digit referencenumerals as those discussed above, but using the prefix “8” simply todistinguish one embodiment from the others. Thus, in FIGS. 9A-B, theemitter body will be referred to as body 820.

In the form illustrated in FIGS. 9A-B, the unitary emitter body 820 ismade of an elastomeric material and has a longitudinal axis. The body820 further defines a pressure reduction flow path 850 and an inlet 830to the pressure reduction flow path 850. The body 820 includes a seriesof rows of baffles 852 g, 852 h, 852 i and 852 j, which are positionedtransverse to the longitudinal axis of the emitter 820 and extend intothe pressure reduction flow passage 850 to form a tortuous passage thatis further laid out in a serpentine manner. In addition, however, theemitter body 820 further defines a plurality of outlet baths. In theform illustrated, the body 820 defines a first outlet bath 842, a secondoutlet bath 843 and a third outlet bath 844. The pressure reduction flowpassage 850 includes an outlet end that opens to the first outlet bath842, and a first passage 845 extends between the first and second outletbaths 842, 843. In a preferred form, at least a portion of the firstoutlet bath or first passage have a first position and a secondposition, the second position being more constrictive to fluid flow thanthe first position.

More particularly, in the form shown, first passage 845 is defined bywall member 847 and moves between a first non-pressurized positionwherein the passage remains in its normal state and the cross-section ofthe passage 845 is at its initial size, and a second pressurizedposition wherein the first passage is elevated or moved toward the innerconduit surface to which the emitter is mounted thereby decreasing thecross-section of the first passage 845 to form a more constrictivepassageway and compensate for the fluid pressure increase experienced bythe emitter 820. The first passage 845 is in the shape of a notch,however, it should be understood that various different size notches orgrooves could be used as desired while still maintaining the pressurecompensation capabilities discussed above. One advantage to smallerconfigurations, however, is that a small surface area is being used toaccomplish the pressure compensation and, thus, the pressurecompensation member can be controlled more easily and can be produced ina way that yields more consistent results emitter to emitter.

In alternate embodiments, it should be understood that the floor of thefirst outlet bath 842 may alternatively be made moveable rather thanfirst passage 845. For example, the floor of first outlet bath 842 maybe configured to move between a first non-pressurized position whereinthe floor remains in its normal state and the cross-section of the bathopening formed by first bath 842 is at its initial size, and a secondpressurized position wherein at least a portion of the floor is pushedor extended into the first bath 842 via increased fluid pressure withinthe conduit to which the emitter 820 is mounted thereby decreasing thecross-section of the bath opening formed by first bath 842 to compensatefor this fluid pressure increase. In still other embodiments, both thefirst passage 845 and first outlet bath 842 may be moveable between suchpositions. However, as mentioned above, in a preferred form, only thefirst passage 845 will be designed to move in such a way because themovement of such a small surface is easier to control and producerepeatable results from emitter to emitter.

Turning back to FIGS. 9A-B, the emitter 820 further defines a thirdoutlet bath 844 and a second passage 846 extending between the secondoutlet bath 843 and the third outlet bath 844. The second passage 846 isdefined by wall members 848 a, 848 b and differs in shape from that offirst passage 845. In a preferred form, neither the second outlet bath843 nor second passage 846 are setup to compensate for pressure andfluid flowing through the second outlet bath 843 is simply allowed topass through to the third outlet bath 844. The conduit to which theemitter 820 is connected will define an outlet opening like drip lineoutlet opening 71 (mentioned with respect to FIG. 1 above) and thisopening may be positioned above either the second or third outlet baths843, 844. In alternate embodiments, it should be understood that if thedesired flow rate may be accomplished through the first passage 845, theemitter 820 may be designed with only one additional outlet bath whichmay either result in combining the second and third outlet baths 843,844 to provide only a second outlet bath, or result in the manufacturerbeing able to reduce the size of the emitter to terminate after thesecond outlet bath 843.

In yet other embodiments, it should be understood that at least aportion of the second outlet bath 843 or second passage 846 may also beconfigured to move between a third position and a fourth position, thefourth position being more constrictive to fluid flow than the thirdposition in order to further compensate for fluid pressure changes ifdesired. For example, in the form illustrated, the floor of the secondbath 843 could be made moveable between a third non-pressurized positionwherein the floor remains in its normal state and the cross-section ofthe bath opening formed by second bath 843 remains at an initial size,and a fourth pressurized position wherein at least a portion of thefloor is pushed or extended into the second bath 843 via increased fluidpressure within the conduit to which the emitter 820 is mounted therebydecreasing the cross-section of the bath opening formed by second bath844 to compensate for this fluid pressure increase. Alternatively, thesecond passage 846 between the second and third outlet baths 843, 844,respectively, could be configured to move so that the cross-section ofthe passage opening reduces in size when moved from a third position toa fourth position. In still other forms, both the second outlet bath 843and second passage 846 could be configured to move in response toincreases in fluid pressure to compensate for same.

In yet other embodiments and as mentioned with respect to the firstpassage 845 above, the second passage 846 may be provided in a varietyof different shapes and sizes. It is preferred, however, to maintain asmaller size and shape for this passage (if setup to compensate forpressure) so that the passage's operation is easier to control and toreproduce on a repeatable results from emitter to emitter. Alternativelyand as mentioned above, no second passage 846 may be provided as thefirst outlet bath 842 may be configured to outlet fluid directly intothe second and final outlet bath.

Turning back to FIGS. 9A-B, the third outlet bath 844 is connected tothe second outlet bath 843 via second passage 846 and further includesprojections or nubs 841 for preventing the third outlet bath 844 fromcollapsing in response to fluid pressure increases. As with theembodiment of FIGS. 8A-G, the rows of baffles 825 g-j of emitter 820 ofFIGS. 9A-B are preferably formed with teeth extending from wall memberswith the teeth being staggered with respect to one another so that theteeth at least partially align with the gaps created between opposingbaffle teeth members to form the tortuous pressure reducing flow passage850 therebetween. Lastly, the emitter 820 preferably includes guiderecess 821 for aligning and inserting the emitter 820 into conduit andfor creating a recessed inlet 831 that is protected from largerobstructions traveling through the conduit in a manner similar to thatdiscussed above in prior embodiments.

As mentioned above, in alternate embodiments, other portions of thefirst, second and third outlet baths 842, 843 and 844 (including firstand second passages 845 and 846) may be configured to move to compensatefor fluid pressure changes. In addition, it should be understood thatother features of earlier embodiments may be incorporated into theembodiment illustrated in FIGS. 9A-B and vice versa. More particularly,any of the above-mentioned features with respect to the variousembodiments discussed herein may be combined or mixed and matched withone another to come-up with alternate embodiments intended to be coveredherein.

An alternate embodiment of an emitter in accordance with aspects of thepresent invention is illustrated in FIGS. 10A-E. In keeping with theabove practice, items in this embodiment that are similar to thosepreviously discussed will be referred to using the same two-digitreference numeral but adding the prefix “9” to distinguish oneembodiment from others. Thus, the emitter illustrated in FIGS. 10A-Ewill be referred to generally by reference numeral 910.

In the embodiment illustrated, emitter 910 has a single piece or unitarybody construction and defines an inlet 930, inlet channel 931, pressurereducing flow channel 950, pressure compensating member or channel 960and outlet 940. The pressure compensating member 960 and outlet 940essentially form first and second baths 942, 943 divided by first andsecond wall members 947 a, 947 b with passage 945 passing therebetween,and a third or final bath 944 separated from the second bath 943 viapassage 946. The emitter 910 includes an inlet protrusion or projection,such as elongated inlet sleeve 932, which extends the inlet opening 930more towards the center or middle of the lumen of the tube 970 intowhich the emitter 910 is mounted (see FIG. 10E). This allows the inlet930 to draw fluid from the center region rather than at acircumferential periphery of the inner lumen of the tube 970 to whichthe emitter is mounted. Since larger grit or other particulates orparticles found in the fluid traveling through the drip line tube 970tend to stay near the inner wall of the tube (near the circumferentialperiphery), having the sleeve 932 project the inlet 930 further into ortoward the center of the inner lumen of the tube 970 helps reduce thepotential that grit or other particulates will enter into and/or clogemitter 910 or prevent it from performing as desired (and particularlythe larger pieces which are more likely to cause a problem with theoperation of the emitter 910).

In the form illustrated, the inlet protrusion 932 forms a sleeveextending out from the emitter body 910 toward the center of the innerlumen of tube 970. The sleeve 932 has a rounded or beveled distal endand defines an inlet channel opening 931 that is generally rectangularin cross-section and connects in fluid communication the outermost inletopening located at the distal end of the inlet sleeve 932 to thetortuous flow passage 950 and, in particular, the pressure reducing flowsection of the flow channel. The inlet sleeve 932 extends from thelongitudinal center of one end of emitter body 920; however, it shouldbe understood that in alternate forms, the inlet sleeve 932 may extendfrom another location on the emitter body 920, such as from a corner orside of the emitter body (as will be discussed further with respect tothe embodiments of FIGS. 12A-15B). It also should be understood thatalthough the inlet sleeve 932 is illustrated as a generally oval orrounded rectangular sleeve in FIGS. 10A-E, the inlet sleeve 932 may beprovided in a variety of different shapes and sizes (including withoutlimitation length and cross-section). One advantage to the rounded edgesof the inlet sleeve 932, however, is that it reduces the number of flatsurfaces located on the emitter 910 which are typically prone tocollecting grit and other particulates (e.g., grit build-up).

In the form illustrated, the emitter body 920 has a height rangingbetween one hundred thousandths of an inch (0.100″) and one hundredfifty thousandths of an inch (0.150″) (see dimension C in FIG. 10E), awidth ranging between two hundred fifty thousandths of an inch (0.250″)and four hundred thousandths of an inch (0.400″), and a length rangingbetween eight hundredths of an inch (0.800″) and one and five hundredthousandths of an inch (1.500″). The emitter body 920 will be insertedinto conventional drip tubing sizes, which vary not only in outerdiameter (“OD”) sizes (e.g., ¼″, ½″, ¾″, 1″, 1.5″, etc.), but also varyin inner diameter (“ID”) sizes due to differences in tube wallthicknesses. Thus, in a preferred form, the height of the inlet sleeve932 (see dimension B in FIG. 10E) will be such that the opening of inlet930 is positioned between twenty and fifty percent (20-50%) of the ID ofthe tubing 970. The following chart provides some exemplary heightranges for the extended inlet sleeve 932 at some of the moreconventional ID tube sizes:

Height Range ID 20% of ID 50% of ID 0.512″ (13 mm) 0.102″ 0.256″ 0.630″(16 mm) 0.125″ 0.315″ 0.709″ (18 mm) 0.142″ 0.354″ 0.787″ (20 mm) 0.157″0.394″

Although the chart indicates a height ranging between one hundred andtwo thousandths of an inch (0.102″) and three hundred ninety-fourthousandths of an inch (0.394″), it should be understood that tubing ofvarying sizes can be used, and thus, the actual height of inlet sleeve932 may be above or below this range. In a preferred form, inlet sleeve932 will be configured to be one half to one times (½× to 1×) the heightof the emitter body 920 (see dimension C in FIG. 10E). Thus, using theheight range specified above, this would give a sleeve height (seedimension B in FIG. 10E) of between fifty thousandths of an inch(0.050″) and two hundred and twenty five thousandths of an inch(0.225″). If it is desirable to keep the size of the emitter 910 down toa minimum, sticking closer to a sleeve 932 that is one half times (½×)the size of the height of the emitter body 920 will be preferred.

The emitter 910 illustrated in FIGS. 10A-E further includes a differentflow passage configuration and, specifically, a different pattern orlayout to the pressure reduction portion of the flow passage and adifferent layout or orientation to the pressure compensation portion ofthe flow passage. More particularly, in the form illustrated, thepressure reduction portion of the flow path is a much more condensedserpentine pattern due to the smaller size of emitter 910 (e.g., emitter910 is approximately one third (⅓^(rd)) the size of the embodimentsdiscussed previously), and the pressure compensation portion 960includes a different orientation but yet still includes two opposingwall members 947 a, 947 b that tapper toward one another to form angledteeth or a notch that can be moved between low fluid pressure positionswherein maximum gaps are provided between upper surfaces of the wallmembers 947 a, 947 b and the surrounding inner surface of the tube 970within which the emitter is mounted and high fluid pressure positionswherein the gaps between the upper surfaces of wall members 947 a, 947 band the inner surface of tube 970 are at their minimum (possibly evenhaving no gap). The movement of the wall members 947 a, 947 b isachieved via movement of the floor of the emitter proximate the wallmembers 947 a, 947 b. Thus, when fluid pressure increases within theinner lumen of tube 970, the floor of the emitter 910 and associatedwall members 947 a, 947 b are moved toward the inner surface of the tube970 thereby causing the cross sectional area of the flow passage throughthe emitter to be reduced at passage 945 to create a pressure drop frombath 942 to bath 943 to account for the increase in fluid pressure. Thisregulation causes the emitter 910 to drip fluid at a generally constantflow rate.

In the form illustrated in FIGS. 10A-E, a recess is formed in thebackside (i.e., bottom or rear) of the emitter 910 below the pressurecompensation portion 960 in order to thin the floor 961 to make it moreresponsive to increases in pressure for the fluid traveling through theinner lumen of tube 970. This recess gives the floor 961 a trampolinetype effect or action and allows wall members 947 a, 947 b to be movedmore easily between their low fluid pressure and high fluid pressurepositions, similar to the moveable wall members discussed above withrespect to prior embodiments. The recess extends beyond the moveablewall portion (i.e., the moveable notch or teeth portion or flipper teethportion) of the flow path and into at least a part of the fixed toothportion of the flow path. This configuration could be used in order toallow the floor 961 of that part of the fixed teeth portion to move inresponse to increases and decreases in fluid pressure in tube or line970 to further help the emitter 910 compensate for such changes in thesystem. Thus, this portion of the fixed height section of the flow pathmay provide both pressure reduction and pressure compensation ifdesired. In alternate forms, however, the thinning of the floor of thefixed teeth portion will be designed not to move in such a mannerdespite the presence of such a recess in which case the fixed portionwill only pressure reduction. It should be understood that in alternateembodiments of the invention recesses of different sizes and shapes maybe used to create trampoline areas of different size and shape toachieve the desired pressure compensation effect (including withoutlimitation those discussed in the embodiments that follow).

In a preferred form, the emitter 910 is made of any material capable ofallowing for the upper surfaces of wall members 947 a, 947 b to be movedup toward the inner surface of tube 970 in order to reduce thecross-section of the flow channel and compensate for increased fluidpressure within tube 970. For example, the emitter 910 may be made ofTPO having a Durometer reading ranging between 25 and 100 (preferablybeing between 50 and 75) and allowing the pressure compensation portion960 to move between five thousandths of an inch (0.005″) and thirtythousandths of an inch (0.030″) and preferably between eight thousandthsof an inch (0.008″) and twenty-two thousandths of an inch (0.022″).

As mentioned above, the emitter illustrated in FIGS. 10A-E isapproximately one third (⅓^(rd)) the size of the emitters illustrated inFIGS. 1A-9B. This size still allows the emitter to operate withindesired pressure compensation parameters, but saves a significant amountin material costs. It alternate forms, the emitter of FIGS. 10A-E may beconfigured so that it is slightly larger and approximately half (½) thesize of the emitters illustrated in FIGS. 1A-9B. For example, this maybe done in order to increase the size of the trampoline area or pressurecompensation area 960 of the emitter 910 in order to improve thepressure compensation performance of the emitter.

In the form illustrated in FIGS. 10A-E, the trampoline area or pressurecompensation area of the emitter makes-up one third (⅓^(rd)) to one half(½) of the overall emitter. In alternate forms, the pressurecompensation portion of the emitter may make-up more or less of theoverall emitter. For example, in a preferred form, the outlet bath wouldmake-up one third (⅓^(rd)) of the emitter and the pressure compensationportion would make-up the remaining two-thirds (⅔rds) of the emitter(meaning there is no pressure reducing portion for grit to get stuck inor clog). Alternatively, a pressure reduction portion could be addedand, if desired, the recess could be extended under the entire pressurereduction portion or fixed teeth portion of the flow passage so that theentire flow path or passage provides pressure compensation. If anemitter with only a pressure compensation portion and outlet bath cannotbe used (i.e., one without a pressure reduction portion), in a preferredform, the pressure reduction portion will be one to one and a half times(1× to 1.5×) the size or area of the pressure compensation portion inorder to provide a desired pressure drop to the fluid passing throughthe emitter 910. In other forms, the pressure reduction portion 950 maybe incorporated into the inlet sleeve 932 and the remaining portion ofthe flow passage extending between the inlet sleeve 932 and the outletbath 940 may be configured to be pressure compensating only.

In the specific embodiment illustrated in FIGS. 10A-E, the pressurecompensation portion of the flow passage has a width ranging between twohundred fifty thousandths of an inch (0.250″) and three hundredseventy-five thousandths of an inch (0.375″) and a length rangingbetween one hundred twenty-five thousandths of an inch (0.125″) andthree hundred seventy-five thousandths of an inch (0.375″). The height(or depth) of the pressure compensation flow path ranges between twentythousandths of an inch (0.020″) and thirty thousandths of an inch(0.030″), with the overall height of the emitter again ranging betweenone hundred thousandths of an inch (0.100″) and one hundred fiftythousandths of an inch (0.150″).

The emitter 910 also includes a root growth inhibiting member, such ascopper insert or body 980, which is positioned proximate to the outletbath 940 to reduce the risk of roots growing into the outlet 940 of theemitter 910. In the form illustrated, the copper insert 980 correspondsin shape to the shape of outlet bath 940 and is, preferably, connectedto the floor of the outlet bath 940 so that it cannot shift and blockflow of fluid through the emitter 910 and out of the outlet 940. In oneform, the copper insert 980 is formed as a plate that is fixed to thebottom of outlet bath 940 via an adhesive. It should be understood,however, that in alternate embodiments, the copper insert 980 may take avariety of different shapes and sizes and may be connected or affixed tothe emitter in a variety of different ways. For example, with respect tosize and shape, in alternate forms, the copper insert 980 may be shapedto fit in only a portion of the outlet bath 940 (e.g., filling only asingle finger of the outlet bath 940 rather than all four fingersillustrated) or in passage 946. In a preferred form, the outlet 940 ofthe emitter 910 will take up no more than one third (⅓^(rd)) of theemitter's total size, thus, the copper insert 980 will preferably have asize that is less than one third (⅓^(rd)) the overall emitter size.

With respect to securing the copper insert 980 to emitter 910, inalternate forms, the insert 980 may be secured to the emitter 910 viaalternate forms of fastening (heat stake, rivet, screw, pin, mating orinterlocking structures (e.g., tongue and groove configuration, balland/or detent, mortise and tenon, etc.), friction or press fitting,etc.). For example, the side wall of the outlet bath 940 may be designedwith a lip or projection that the copper insert gets pushed past duringinstallation in order to secure the copper insert 980 in position orprevent the insert 980 from interfering with the flow of fluid throughthe emitter 910 while generally maintaining the insert 980 in a desiredlocation or position. In such a form, the lip may be located in a singlespot on a side wall of the outlet bath 940. Alternatively, the lip maycomprise multiple lips extending out from one or more side walls of theoutlet bath 940. In still other forms, the lip may comprise a continuouslip extending around the entire outlet bath 940 or all side walls of theoutlet bath 940.

In the form illustrated in FIGS. 10A-E, the emitter 910 may be providedin a plurality of different flow rates (e.g., 1 GPH, 2 GPH, 4 GPH,etc.). The emitter 910 may be altered in a variety of different ways tocontrol flow rate of the emitter. For example and without limitation,the gap between moveable wall members may be adjusted to achievedifferent flow rates, the cross-sectional area of the flow passage ofthe emitter may be altered, and the number of fixed or moveable teethcan be adjusted to achieve different flow rates. In one form, the gapbetween the moveable wall members 947 a, 947 b (illustrated as passage945) may be widened or narrowed in order to change the cross-sectionalarea of the flow passage to provide emitters of differing flow rates.For example, the gap between wall members 947 a, 947 b can be widened toallow more fluid to flow through the emitter to provide an emitter witha higher GPH flow rate. Conversely, the gap between wall members 947 a,947 b can be narrowed in order to let less fluid flow through theemitter to provide an emitter with a lower GPH flow rate.

In another form, the cross-sectional area of other portions of the flowpassage may be changed to provide emitters with different flow rates.For example, the floor or depth of the flow passage (either in thepressure reduction portion or the pressure compensation portion, orboth) may be lowered to create a passage with a larger cross-sectionalarea that allows more fluid to flow through the emitter, therebyproviding an emitter with a higher flow rate. Conversely, the floor ofthe flow passage may be raised to reduce the cross-sectional area of theflow passage so that less fluid can flow through the emitter, therebyreducing the flow rate of the emitter.

In still other forms, the number of teeth can be adjusted for the flowpassage to provide emitters with different flow rates. For example, inone form, the number of fixed teeth (i.e., fixed-height teeth ornon-moving teeth) may be increased to achieve a more tortuous path foradditional pressure reduction and, thus, lower flow rate. Conversely,the number of fixed teeth can be reduced to achieve a less tortuous pathfor less pressure reduction and, thus, a higher flow rate.Alternatively, the number of moveable teeth (e.g., wall members 947 a,947 b) may be increased or decreased to achieve more or lessconstrictions to produce greater or less pressure compensation,respectively, for achieving different flow rates.

In still other forms, the height of the moveable teeth may be adjustedto provide emitters with different flow rates. For example, moveableteeth having greater height may be used to reduce the amount of pressurerequired in order to saturate the pressure compensation section of theflow passage. Conversely, moveable teeth having less height may be usedto increase the amount of fluid pressure the emitter can account forbefore reaching its saturation point.

In FIGS. 11A-E, an alternate form of emitter is illustrated havingmoveable teeth that can be adjusted to provide emitters with differentflow rates as discussed above. In keeping with the above practices,items associate with this emitter that are similar to those discussedabove will use the same two digit reference numeral but having theprefix “10” added to distinguish one embodiment from the others. Thus,in FIGS. 11A-E, the emitter is referenced as emitter 1010 and includes asingle piece or unitary emitter body 1020 defining an inlet 1030 andoutlet 1040. Like the embodiment of FIGS. 10A-E, the emitter 1010 ofFIGS. 11A-E includes an elongated inlet protrusion, such as sleeve 1032,which is centrally located on one end of the emitter body 1020 andallows the emitter 1010 to draw fluid from the tube within which it isinstalled from a region closer to the center of the inner lumen of thetube and away from where larger pieces of grit or particles collectalong the inner wall of the tube. The inlet sleeve 1032 preferablyincludes rounded edges to reduce the number of flat surfaces located onthe emitter where grit build-up can occur. The emitter 1010 alsoincludes outlet walls 1041 a, 1041 b, 1041 c, which support the outletbath 1040 and prevent the floor of the outlet bath 1040 from collapsingtoward the adjacent inner surface of the tube as fluid pressureincreases within the supply line or tube. A root growth inhibitingmember, such as copper insert 1080 is also present in the outlet bath1040 to hinder roots from obstructing the operation of the emitter 1010.

Unlike the embodiment of FIGS. 10A-E, however, the embodiment of FIGS.11A-E includes a plurality of moving teeth 1062 staggered apart from andopposing one another in the pressure compensation section 1060 of theemitter 1010. The emitter 1010 has a notch or recess formed on thebackside forming the trampoline area of the emitter so that the floor1061 of the flow path can move the moveable teeth 1062 between their lowpressure position wherein the upper surfaces of the moveable teeth arespaced apart from the inner surface of the tube or drip line withinwhich the emitter is installed and their high pressure position wherethe floor 1061 pushes the teeth up toward the inner surface of the tubeuntil the upper surfaces of the moveable teeth 1062 engage the innersurface of the tube. The movement of the moveable teeth or flippers 1062into their high pressure position reduces the cross-sectional area ofthe flow passage so that less fluid can travel through the emitter 1010as a means for compensating for increased line pressure within the tubeand to keep the flow rate of fluid through the emitter 1010 relativelyconstant.

The dimensions specified for the emitter of FIGS. 10A-E apply equallywell for the emitter of FIGS. 11A-E, and it should be understood thatthe alternate embodiments discussed with respect to FIGS. 10A-E equallyapply for the embodiment of FIGS. 11A-E, as well. For example, inalternate forms, the height of inlet sleeve 1032 may be adjusted asneeded to get the emitter to draw fluid more from the center region ofthe tube. In addition, the emitter could be configured with a pressurereduction flow passage only rather than both a pressure reductionportion and a pressure compensation portion. In still other forms, thepressure reduction portion could be incorporated into the inlet sleeve1032 with the remainder of the flow passage between the sleeve 1032 andthe outlet bath 1040 being pressure compensating.

Similarly, it should be understood that the alternate ways for providingemitters of varying flow rate equally apply to the embodiment of FIGS.11A-E. For example, the depth of the flow passage or a portion of theflow passage could be adjusted to provide emitters of varying flow rates(e.g., 1 GPH, 2 GPH, 4 GPH, etc.). Alternatively, the height or numberof the teeth members (either the fixed or the moveable) can be adjustedto provide emitters of varying flow rates. In still other forms, the gapor spacing between the teeth members may be adjusted to provide emittersof varying flow rates.

Another emitter embodiment in accordance with the invention is disclosedin FIGS. 12A-B. In keeping with the above practice, items with respectto this emitter that are similar to those discussed in the embodimentsabove will use the same two-digit reference numeral but add the prefix“11” to distinguish one embodiment from another. Thus, in FIGS. 12A-B,the emitter is referenced by reference numeral 1110 and comprises aunitary body 1120 that defines an inlet opening 1130, flow passage andoutlet bath 1140. Like the embodiments of FIGS. 10A-11E, the emitter1110 of FIGS. 12A-B includes an elongated inlet 1032, outlet bath walls1141 a, 1141 b and 1141 c, and a root growth inhibiting member, such ascopper insert 1180 (shown exploded from the emitter body for purposes ofillustrating its presence). Unlike the embodiments of FIGS. 10A-11E,however, the emitter 1110 of FIGS. 12A-B has an elongated inlet sleeve1032 that is positioned at a corner of the emitter body 1120 rather thancentrally located on the end of the emitter. This configuration allowsthe length of the pressure reduction portion 1250 of the tortuous flowpassage to be maximized as it starts from the corner of the emitter body1220, rather than in the middle of the body 1220, as is done in theemitter of FIGS. 10A-11E.

Emitter 1110 of FIGS. 12A-B further includes a different configurationor layout to the pressure compensation portion 160 of the emitter 1110.Specifically, the emitter uses first and second moveable wall members1147 a, 1147 b, respectively, to compensate for increase in fluid linepressure. When in the low pressure position (illustrated), the walls1147 a, 1147 b and floor 1161 remain in their static state and allowfluid to flow over the top surfaces of walls 1147 a, 1147 b. However,when fluid line pressure builds, the floor or trampoline area 1161 ofpressure compensating portion 1160 moves upward toward the inner surfaceof the tube to which the emitter is mounted until the upper surfaces ofwalls 1147 a, 1147 b seal against the inner surface of the tube (orapproach this point), which reduces the cross-sectional area of thepassage 1145 through which the fluid passes and thereby compensates forthe increase in fluid line pressure.

As previously mentioned, the alternative embodiments covered above applyequally to the embodiment of FIGS. 12A-B. For example, although thecopper insert 1180 is adhered to the floor of the emitter outlet bath1140, it should be understood that in alternative embodiments the insert1180 could be connected to the emitter in a variety of different ways(e.g., heat stake, rivet, screw, pin, mating or interlocking structures(e.g., tongue and groove configuration, ball and/or detent, mortise andtenon, etc.), friction or press fitting, etc.). Similarly, thedimensions of the emitter 1110 or any of its parts could be altered asdiscussed above in order to cater to a particular application.

Yet another form of emitter in accordance with the invention isillustrated in FIGS. 13A-B. In keeping with the above, items that aresimilar to those discussed above will be numbered using the same latertwo digit reference numeral but adding a prefix “12” to distinguish oneembodiment from the others. In the form illustrated, the emitter 1210includes a single piece body 1220 defining an inlet opening 1232, flowpath and outlet 1240. The emitter further includes an inlet protrusion,such as sleeve 1232, which extends from a corner of the emitter body tomaximize the length of the tortuous flow passage 1250. A pressurecompensation configuration 1260 similar to that described with respectto FIGS. 12A-B is also disclosed in which moveable walls 1247 a, 1248 bare allowed to move from a low pressure position to a high pressureposition in response to increased line pressure to help compensate forthe increase in pressure.

Unlike the prior embodiments of FIGS. 10A-12B, however, emitter 1210 ofFIGS. 13A-B includes a filter in the distal end of the inlet sleeve 1232to block relatively large particles (e.g., grit, particulates, etc.).Specifically, the distal end of sleeve 1232 includes a plurality ofslots, such as filter channels 1232 a, 1232 b, 1232 c, 1232 d, 1232 eand 1232 f that are used to help block larger particles of debris orgrit from entering into the inlet channel 1231 of emitter 1210. Thenetwork of channels 1232 a-f further reduces the likelihood that a pieceof debris or build-up of debris could block all fluid from flowingthrough the emitter 1210. Rather, such large objects would likely beblocked by the outermost surfaces of the inlet sleeve 1232, while fluidis allowed to work its way through the channels 1232 a-f and continue toflow through emitter 1210.

The emitter 1210 of FIGS. 13A-B further includes projections or nubs,such as posts 1241, in the outlet bath 1240 instead of walls (like thoseshown in FIGS. 10A-12B). The posts 1241 prevent the floor of the outletbath 1240 from collapsing in toward the inner surface of the tube inwhich the emitter is mounted when line pressure increases in the tube sothat the emitter continues to allow fluid to flow through the emitter asdesired. In view of this configuration, the shape of the root growthinhibiting member (e.g., copper insert 1280) is also changed to matewith the posts 1241. Specifically, the insert 1280 defines a pluralityof mating openings that correspond to the location of posts 1241 so thatthe insert 1280 can be positioned within the outlet bath 1240 of theemitter 1210. In a preferred form, the posts 1241 and openings in insert1280 are configured to allow the insert 1280 to rest flush against thefloor of the outlet bath 1240 so that the insert 1280 can be adhered tothe floor of the outlet bath 1240. This may require the insert 1280 tohave a slight bend that tracks the curvature of the floor of the outletbath 1240 (if any). However, in alternate embodiments, the posts 1241and openings in insert 1280 could be configured to engage one another ina friction fit so that no adhesive is necessary. This configuration alsocould allow the plate to be held at a different position with respect tothe posts 1241 instead of adjacent to the floor of outlet bath 1240(although such a position is possible with this configuration as well).For example, it may be deemed desirable to position the plate 1280closer to the outlet opening in the tubing to which the emitter body1220 is mounted. In such a case, the size of the openings in the insert1280 could be made so that the insert 1280 rests near the top of theposts 1240.

As mentioned above, the various alternative embodiments discussed witheach embodiment are equally applicable to other embodiments, includingwithout limitation the embodiment of FIGS. 13A-B. For example, inalternate forms, the insert 1280 does not have to fill the entire outletbath 1240, but rather, could be a narrower plate that covers a smallerportion of the outlet bath 1240. In one form, the insert 1280 may takethe form of a narrow plate that only has openings for one post 1241 orone row of posts. In another form, the insert 1280 may be configuredwith a different shape if desired (e.g., a triangular shape, variouspolygonal shapes, round or curved shapes, symmetrical shapes,asymmetrical shapes, non-planar shapes, etc.). For example, in one form,the insert 1280 may be configured to have a non-planar shape wherein theinsert 1280 has a chimney portion that extends up from a planar portionto create a bulge in the tube once the emitter is mounted into thetubing which can then be used to locate and cut open the outlet in thetube to complete manufacturing process and provide a finished emitterand/or drip line. With this configuration the chimney of the copperinsert 1280 would extend up into the tube outlet opening like a sleeveto further deter roots from growing toward or near this portion of theemitter and/or tubing. In still other forms, the insert 1280 may startout as one shape but be altered during the manufacturing process. Forexample, the insert 1280 may start out as a planar plate, but when theoutlet opening is punched through the tube wall proximate the outletbath 1240, the plate also may be punched down into the floor of theoutlet bath 1240 leaving a dent in the insert 1280. This may helpfriction fit the insert 1280 to the emitter 1210 and/or may punch aportion of the insert 1280 partially into the floor of the emitter bath1240 (but not through) in order to fasten the insert 1280 to the emitter1210.

Another difference between the embodiment of FIGS. 13A-B and the priorembodiments of FIGS. 10A-12B is that the recess on the backside of theemitter that defines the trampoline area of the pressure compensationportion 1260 is smaller in size and shape and restricted to the pressurecompensation portion 1260, rather than extending further under thetortuous passage of the pressure reduction portion 1250. This smallertrampoline area of pressure compensation portion 1260 is designed tomake the emitter 1210 less responsive to supply line pressure increases.Specifically, the smaller area of the recess or trampoline area of thepressure compensation portion 1260 reduces the amount of movement floor1261 will have and/or requires greater pressure to move wall members1247 a, 1247 b to seal against the inner surface of the tube.

Another exemplary emitter is illustrated in FIGS. 14A-B. In keeping withthe above, items that are similar to those discussed above with respectto prior embodiments will be marked designated with the same lattertwo-digit reference numeral but include the prefix “13” to distinguishone embodiment from another. Thus, in FIGS. 14A-B, the emitter isdesignated as emitter 1310 and includes a body 1320 that defines andinlet 1330, an outlet 1340 and a tortuous passage connecting the inlet1330 and outlet 1340. Like the embodiment of FIGS. 13A-B, emitter 1310of FIGS. 14A-B has an off-center inlet 1330 that extends down from thecorner of the emitter body 1320 thereby allowing the length of thepressure reduction flow passage 1350 to be maximized. The emitter 1310also includes an inlet projection, such as sleeve 1332, with an integralfilter in the form of filter channels 1332 a, 1332 b, 1332 c, 1332 d,13332 e and 1332 f, which allows the emitter to draw fluid from closerto the center or center region of the inner lumen of the tube in whichthe emitter is mounted and filter out relatively larger grit particlesfrom entering the emitter 1310. The emitter further includes a smallerpressure compensation portion 1360 and a root growth inhibitor member inthe form of copper insert 1380 which is positioned on outlet projectionsor nubs 1341.

Unlike the embodiment of FIGS. 13A-B, however, the emitter 1310 of FIGS.14A-B includes a plurality of moveable teeth or flippers 1352 that movebetween a low fluid pressure position wherein the upper surfaces of theflippers are spaced apart from the inner surface of the tube in whichthe emitter 1310 is mounted and a high fluid pressure position whereinthe upper surfaces of the flippers are moved toward the inner surface ofthe tube to reduce the cross-sectional area of the flow passage 1360 inresponse to increased fluid pressure in order to make the emitter 1310pressure compensating. In the form illustrated, the flippers aregenerally triangular in shape and taper from a taller end 1352 n to ashorter distal end 1352 o. As best illustrated in FIG. 14B, the smallersize of the trampoline area 1360 for the emitter 1310 means that agreater amount of fluid pressure will be required in order to move theflippers between their low and high fluid pressure positions. In analternate form, the trampoline area 1360 may be expanded like that shownin FIGS. 10A-12B, in order to make the pressure compensating trampolinearea easier to move and, thus, more responsive to increases anddecreases in fluid pressure. More particularly, the size of thetrampoline area on one side of the emitter (e.g., see trampoline 1360 onFIG. 14B) may be made larger than the pressure compensating portion onthe other side of the emitter (e.g., see moveable teeth of flippers 1360on FIG. 14A) in order to make the emitter more responsive to fluidpressure increases or decreases. This increase in trampoline area 1360may further be designed to convert a portion of the pressure reductionflow channel 1350 into part of the pressure compensating member 1360(e.g., by allowing the floor of the pressure reduction flow channel tomove in response to fluid pressure increases and decreases), but doesnot have to if it is desired to keep the pressure reduction flow channel1350 separate and apart from the pressure compensation portion 1360.

As mentioned above, it should be understood that features of any of theabove-mentioned embodiments may be incorporated into the emitter 1310 ofFIGS. 14A-B if desired. For example, outlet bath walls could be used inlieu of or in addition to post members 1341. Similarly, alternate flowchannel patterns and orientations may be used. The size of the emitter1310 also may be adjusted within the range specified above.

Another emitter embodiment is illustrated in FIGS. 15A-B. In keepingwith the above practice, features of this embodiment that are similar tothose discussed above will use the same latter two-digit referencenumeral but include the prefix “14” in order to distinguish oneembodiment from the others. Thus, the emitter will be referenced usingreference numeral 1410 for convenience.

In the form illustrated, emitter 1410 has a larger shape more akin tothe embodiments of FIGS. 1A-9B. Unlike those prior embodiments, however,emitter 1410 includes a smaller inlet channel or raceway 1431 that ispositioned in one end or half of the emitter rather thancircumnavigating the entire periphery of the emitter. In addition, theemitter 1410 includes a root growth inhibitor member, such as copperinsert 1480, and defines a smaller pressure compensation or trampolinearea 1460. In the form illustrated, the copper insert 1480 forms a platewith openings corresponding to the post members 1441 of outlet bath 1440so that the plate 1480 can be disposed in the outlet bath 1440 proximatethe emitter outlet opening of the tube in which the emitter 1410 ismounted or affixed.

The pressure compensating portion 1460 of emitter 1410 includes aplurality of moveable teeth or flippers that are orientated such thatthey continue the serpentine pattern of the pressure reduction flowpassage 1450. The teeth move between a low fluid pressure position(shown) wherein the upper surfaces of the teeth are spaced apart fromthe inner surface of the tube within which the emitter 1410 is mountedand a high fluid pressure position wherein the upper surfaces of theteeth are moved toward, if not into engagement with, the inner surfaceof the tube within which the emitter is mounted in order to reduce thecross-sectional area of the flow passage to compensate for increases influid pressure.

Another exemplary embodiment in accordance with the invention disclosedherein is illustrated in FIGS. 16A-B. In keeping with above practice,items of this embodiment that are similar to those discussed above willuse the same latter two-digit reference numeral but include the prefix“15” to distinguish one embodiment from others. Thus, the emitter ofFIGS. 16A-B will be referred to generally as emitter 1510. In the formillustrated, the emitter 1510 includes a unitary emitter body 1520defining an inlet 1530, outlet 1540 and tortuous flow passage connectingthe inlet 1530 and outlet 1540. In addition, the emitter 1510 furtherincludes a carrier 1590 connected to at least a portion of the emitterbody 1520 to assist with the insertion of the emitter 1510 into tubingor line to form a finished drip line. For example, the elastomericmaterial of emitter body 1520 can increase the amount of friction thatexists between the emitter body 1520 and the insertion equipment used toinstall the emitter body 1520 into tubing. Such an increase in frictioncan lead to the binding-up of the insertion equipment and can ultimatelycause the process to be stopped while the insertion equipment andemitters are cleared of obstructions and/or reorganized for properinsertion. To prevent this, the carrier 1590 may be used to smoothlyguide the emitter body 1520 through the insertion tool and into tubingto form a finished emitter and drip line product.

In the form illustrated in FIGS. 16A-B, the carrier forms a skirt memberthat covers at least a portion of the lower and side surfaces of theemitter body 1520 as these are the surfaces used by the insertion toolto place the emitter into tubing. In the form illustrated, the carrier1590 forms a generally rectangular skirt member that has vertical andhorizontal wall portions 1590 a, 1590 b (respectively) and defines alarge rectangular opening in the middle of the carrier to provide fluidaccess to the bottom surface of emitter body 1520. The vertical wallmember allows the carrier 1590 to form a recess or cup for nesting atleast a portion of the emitter body 1520 in and helps prevent lateralmovement of the emitter body 1520 along the x and y axes in the carrier1590. In a preferred form, the carrier 1590 is connected or fastened tothe emitter body 1520 to further assist in preventing longitudinalmovement of the emitter body 1520 along the z axis in the carrier 1590.

In the form illustrated, the carrier 1590 is made of a polyethylene andthe emitter body 1520 is made of a thermoplastic or thermosettingelastomeric (e.g., TPO) and the carrier 1590 is connected or fastened tothe emitter body 1520 via an adhesive. It should be understood, however,that in alternate embodiments the carrier 1590 and emitter body 1520 maybe connected in a variety of different ways including withoutlimitation, heat staking, thermal bonding, friction fit, matingstructures (such as ball and detent, tongue and groove, mortise andtenon, etc.), set screws, etc. or using the shape of either of thestructures themselves (e.g., as will be discussed further with respectto FIGS. 17A-B below). In a preferred form, the elastomeric emitter 1520and carrier 1590 will be formed in a two-step molding process witheither the body 1520 or carrier 1590 being formed in a first step andthe other of the body 1520 or carrier 1590 being formed in a second stepwhile still remaining in the same mold. For example, the carrier 1590could be overmolded onto the body 1520 or, conversely, the body 1520could be overmolded onto the carrier 1590. Overmolding one over theother in a single mold will help reduce the manufacturing time it takesto create the emitter unit and, thus, speed-up the manufacturing processfor producing the final drip line product.

Emitter 1510 is similar to emitter 1010 of FIG. 11A-E, however, theinlet sleeve 1732 does not extend all the way to the forward edge ofemitter body 1520 so that it will not interfere with the bracket orcarrier 1590 extending around the periphery of the emitter body 1520. Itshould also be understood that in alternate embodiments a carrier may beused with any of the above-mentioned emitter embodiments. In addition,although the carrier of FIGS. 16A-B is in the form of a rectangularbracket with an open middle area so that the carrier 1590 only coversthe outer periphery of the lower surface of the emitter body 1520, itshould be understood that in alternate embodiments more or less of theemitter body 1520 may be covered by the carrier. For example, in oneform, the carrier 1590 may form a solid rectangular structure coveringthe entire lower surface of the emitter body 1520 rather than having alarge open middle area. However, in a preferred form, the carrier 1590will define an opening that is at least as big as the pressurecompensating portion of the emitter body 1520 (e.g., the trampoline areaor recess in the bottom of body 1520) in order to provide fluidcommunication between the fluid in the drip line or tube within in whichthe emitter is mounted and the pressure compensation portion 1560 of theemitter 1520. In another form, the carrier 1590 may define a pluralityof openings rather than one middle opening in order to further cut downon material costs so long as a sufficient amount of material is providedfor the carrier 1590 so that it allows the emitter body 1520 to besmoothly moved through the insertion tool and into tubing. Theseplurality of openings may be located in the horizontal or bottom surfaceof the carrier 1590 and/or in the vertical or side surfaces of thecarrier 1590 and may be made in a variety of different sizes and shapes(e.g., angled rectangular slots, rounded slots, circular openings,triangular openings, symmetrical designs, asymmetrical designs, etc.).

Similarly, although the carrier 1590 of FIGS. 16A-B illustrate a designthat only covers a portion of the sides or side walls of the emitterbody 1520, it should be understood that in alternate embodiments thecarrier may be designed to cover more or less of the side walls of theemitter body 1520 (both vertically and horizontally). For example, inone form, the carrier 1590 may be designed with a skirt member having avertical side wall that covers the entire side of the emitter body 1520.In such a form, the emitter body 1520 would likely not be designed witha notch or shoulder recess for receiving the carrier 1590 (like thenotch or shoulder recess illustrated in FIGS. 16A-B), but rather wouldpreferably have a planar side wall that the carrier 1590 simply covers.Again, the side wall of carrier 1590 could be designed with one or moreopenings to reduce or save on material costs associated with the carrier1590 (as will be discussed further below with respect to FIGS. 17A-B).In other forms, the vertical side wall of carrier 1590 may be designedto cover only that portion of the side wall of emitter body 1520necessary to ensure smooth movement of the emitter body 1520 through theinsertion tool and into tubing. For example, in some forms the verticalside wall may not extend all the way around the side of emitter body1520, but rather may only cover a portion of the side wall of emitterbody 1520.

In another form, the carrier 1590 may be designed with no vertical wallextending about the side of the emitter body 1520. For example, if theinserter or insertion tool used to install the emitter body 1520 intotubing only contacts the bottom surface of the structure it isinserting, the carrier 1590 could be designed to only cover the bottomsurface of the emitter body 1520 as that is all that is needed to ensuresmooth movement of the emitter body 1520 through the insertion tool andinto the tubing. As mentioned above, in such a form, the carrier body1520 could cover as much or as little of the bottom surface of theemitter body 1520 as desired and could define one or more openings inthe bottom surface in order to save material costs and to provide fluidcontact to the bottom surface of the emitter body 1520 at least wherethe pressure compensation portion of the emitter is located (e.g., thetrampoline area or recess on the bottom side of the emitter body). Inthe form illustrated, the carrier 1590 remains connected to the emitterbody 1520 after the emitter is connected to the inner surface of thetubing and remains connected thereafter. It should be understood that inalternate embodiments, however, the carrier 1590 may be designed todisengage from the emitter body 1520 once the emitter body 1520 isconnected to the inner surface of the tube if such a configuration isdesired. For example, the carrier 1590 could be returned to theinsertion tool to load another emitter body 1520 or could simply dropoff into the tubing and blown out of the tubing before shipping.

Another emitter in accordance with the invention is disclosed in FIGS.17A-B. In keeping with the above-practice, features of this embodimentthat are similar to those previously mentioned will be referenced usingthe same latter two-digit reference numeral but adding the prefix “16”to distinguish one embodiment from others. Thus, in FIGS. 17A-B theemitter will be referenced as emitter 1610. In the form illustrated, theemitter 1610 looks similar to the embodiment of FIGS. 16A-B and 10A-Eand includes a body 1620 that defines an inlet opening 1630 and outletbath 1640 with a tortuous fluid passage therebetween. Unlike priorembodiments, however, the emitter 1610 includes a carrier or bracket1690 that captures portions of both the bottom and top of the emitterbody 1620. More particularly, the bottom portion of carrier 1690includes horizontal and vertical wall members 1690 a, 1690 b,respectively, similar to those illustrated in FIGS. 16A-B. In addition,the carrier 1690 defines a large rectangular inner opening like thecarrier 1590 of FIGS. 16A-B. Unlike prior embodiments, however, thecarrier 1690 further includes an upper bracket portion 1690 c thatextends above an upper portion of the emitter body 1620.

In the form illustrated, the body 1620 forms a recess 1620 a and lip1620 b that corresponds in shape to the upper bracket 1690 c so thatwhen the carrier 1690 is installed on the emitter body 1620 the uppersurfaces of lip 1620 b and upper bracket 1690 c are flush with oneanother. This configuration allows the upper surfaces of the upperbracket 1690 c and emitter body parts (e.g., lip 1620 b, outlet walls1641 a, 1641 b, 1641 c, and walls 1652 g-m, etc.) to make contact withthe inner surface of the tube when the emitter is installed therein sothat fluid will properly flow through the inlet, along the pressurereduction portion 1650 and the pressure compensation portion 1660 of thetortuous fluid passage and into outlet bath 1640. The upper bracket 1690c is spaced apart from the lower bracket portion made-up of vertical andhorizontal wall members 1690 a, 1690 b via risers or spacers, such asposts or stanchions 1690 d, located at the corners of the carrier 1690and emitter body 1620. Thus, the carrier 1690 defines a plurality ofopenings which saves on material costs and reduces the weight of theoverall emitter 1610. As with the embodiment in FIGS. 16A-B, the inletsleeve 1632 is recessed in from the edge of the emitter body 1620 orinset toward the center of the emitter body 1620 and away from the edgein order to allow the carrier 1690 to connect around the periphery ofthe emitter body 1620 (e.g., in order to allow bottom wall member 1690 bto engage the bottom surface of emitter body 1620 about the periphery ofthe body 1620.

In the form illustrated in FIGS. 17A-B, the carrier 1690 captures theemitter body 1620 between the upper and lower bracket portions 1690 cand 1690 a,b, respectively, and the stanchions 1690 d, and prevents theemitter body from moving laterally along the x and y axes andlongitudinally along the z axis. This configuration secures the carrier1690 to body 1620 without the need for further fastening such as byadhesive, bonding, etc., however, additional fasteners can be used ifdesired. In addition, the upper surface of upper bracket 1690 c furtherprovides a material and surface that can assist in the connection of theemitter to tubing. With the configuration of FIGS. 17A-B, cross linkingbetween the emitter and the tugging could be enhanced by using the uppersurface of upper bracket 1690 c to ensure proper bonding between theemitter and the tubing.

As with the embodiment of FIGS. 16A-B, emitter body 1620 and carrier1690 of FIGS. 17A-B are preferably made of an elastomeric material and aplastic polymer, respectively. In the form shown, the elastomeric body1620 is made of TPO and the carrier 1690 is made of polyethylene. Thetubing into which the emitter is inserted is also made of a plasticpolymer, such as polyethylene. In a preferred form, the component ismanufactured using a two-step molding process and a single mold whereineither the emitter body 1620 is made and then overmolded with thecarrier 1690 or vice versa without the need to remove the structure fromthe mold before beginning the overmolding process. The component is theninserted into tubing and thermally bonded thereto during the extrusionof the tubing with the carrier 1690 providing for smooth passage of theemitter body 1620 through the insertion tool and into the tubing.

It should be understood that although two carrier embodiments have beenillustrated in FIGS. 16A-17B, the carrier may be provided in a varietyof different shapes and sizes. It also should be understood that variousaspects of any of the above-mentioned embodiments may be combined withone another in order to provide a finished emitter and/or drip line ortubing. For example, the carrier of FIGS. 17A-B may be configured foruse with the embodiment of FIGS. 1A-J. Alternatively, a portion of thecarrier of FIGS. 17A-B may be used with one of the prior embodiments. Inkeeping with the latter, FIGS. 18A-B show another emitter in accordancewith the invention, wherein a portion of the bracket of FIGS. 17A-B isused to assist in bonding an emitter similar to that depicted in FIGS.11A-E to tubing. As with above embodiments, features of the emitter ofFIGS. 18A-B that are similar to those discussed above will use the samelatter two-digit reference numeral but include the prefix “17” todistinguish this embodiment from others. Thus, the emitter will bereferred to as emitter 1710, which includes an inlet 1730, outlet 1740and tortuous flow passage extending therebetween including a pressurereduction passage 1750 and pressure compensating passage 1760.

In FIGS. 18A-B, the emitter body 1720 defines a recess formed byhorizontal wall 1720 a and vertical wall or lip 1720 b which areconfigured to receive bracket 1790. The depth and width of recess 1720 aand lip 1720 b are such that bracket 1790 is positioned so that its sidewall is flush with the side of emitter body 1720 and its upper surfaceis flush with the upper surfaces of lip 1720 b. The depth and width ofthe recess formed by surface 1720 a and lip 1720 b will preferably allowfor easy overmolding of the bracket 1790 over emitter body 1720 in atwo-step molding process using the same mold. It should be understood,however, that the emitter could also be formed using two separatelymolded pieces that are later connected to one another. With such aconfiguration, the lip 1720 b forms a shoulder that aligns andorientates the bracket 1790 into its position on emitter body 1720. Inthe form illustrated, the bracket 1790 could be positioned in twoorientations with one being illustrated in FIGS. 18A-B and the otherconsisting of the bracket pivoted one hundred and eighty degrees (180°).In alternate forms, the bracket 1790 and body 1720 could be configuredto only allow assembly in one orientation, such as by adding matingstructures that need to be aligned or by using shapes that onlycorrespond with one another in one orientation. As mentioned above,however, in a preferred form, the bracket 1790 is simply molded over theemitter body 1720 using a two-step molding process and a single moldand, thus, orientation of the bracket 1790 is irrelevant as it is notassembled as a separately molded, two piece component.

With this configuration, the upper surface of bracket 1790 will be flushwith or maintain the same radius of curvature as the upper surfaces ofthe remaining emitter body parts (e.g., uppers surfaces of outlet walls1741 a-c, flow passage walls 1752 g-m, etc.) so that the emitter body1720 and bracket 1790 will mount cleanly to the inner surface of thetubing within which the emitter is mounted and that fluid will properlyflow through the inlet 1730, flow passage and outlet 1740. The bracket1790 may further be made of a material that bonds well with the tubingto enhance cross-linking or bonding problems between the emitter andtubing.

FIGS. 19A-C illustrate yet another embodiment of an emitter inaccordance with the invention disclosed herein. In keeping with priorpractice, items of this embodiment that are similar to those discussedpreviously will be identified using the same latter two-digit referencenumeral, but adding the prefix “18” in order to distinguish thisembodiment from others. Thus, the emitter will be referred to as emitter1810, which includes an inlet 1830, outlet 1840 and tortuous flowpassage extending therebetween or located intermediate the inlet 1830and outlet 1840. In a preferred form, the tortuous flow passage includesa pressure reduction passage 1850 and pressure compensating passage1860, and the emitter is configured in an in-line non-cylindricalemitter construction for attachment to only a portion of an innercircumference or surface of the drip line tube within which the emitteris installed (e.g., attachment to an inner circumference of one hundredeighty degrees (180°) or less, and preferably less than ninety degrees(90°)).

As with prior embodiments, the emitter 1810 is formed of an integral orunitary elastomeric material that defines the inlet 1830, outlet 1840and passages located therebetween. The emitter also includes an inletprotrusion or projection 1832 like the embodiment discussed in FIGS.10A-E above. The elongated inlet protrusion 1832 forms a sleeve whichextends the inlet opening 1830 more towards the center or middle of thetube into which the emitter 1810 is mounted (in a manner similar to thatshown if FIG. 10E). This allows the inlet 1830 to draw fluid from thecenter region of the tubing rather than at a circumferential peripheryof the tubing to which the emitter is mounted. Since larger grit orother particulates or particles found in the fluid traveling through thedrip line tubing tend to stay near the inner wall of the tube (near thecircumferential periphery), having the sleeve 1832 project the inlet1830 further into or toward the center of the tube helps reduce thepotential that grit or other particulates will enter into and/or clogemitter 1810 or prevent it from performing as desired (and particularlythe larger pieces of grit or other particulates which are more likely tocause a problem with the operation of the emitter 1810).

In the form illustrated, the sleeve or inlet protrusion 1832 has arounded or beveled distal end and defines an inlet channel opening 1831that is generally rectangular in cross-section and connects in fluidcommunication the outermost inlet opening located at the distal end ofthe inlet sleeve 1832 to the tortuous flow passage 1850 and, inparticular, the pressure reducing flow section 1850 of the flow channel.The inlet sleeve 1832 extends from the longitudinal center of one end ofemitter body 1820; however, it should be understood that in alternateforms, the inlet sleeve 1832 may extend from another location on theemitter body 1820, such as from a corner or side of the emitter body (asdiscussed with prior embodiments). It also should be understood thatalthough the inlet sleeve 1832 is illustrated as a generally oval orrounded rectangular sleeve in FIGS. 19A-C, the inlet sleeve 1832 may beprovided in a variety of different shapes and sizes (including withoutlimitation length and cross-section). One advantage to the rounded edgesof the inlet sleeve 1832, however, is that it reduces the number of flatsurfaces located on the emitter 1810 which are typically prone tocollecting grit and other particulates (e.g., grit build-up). Forexample, over time a film may build up on flat surfaces of the emitterdue to prolonged exposure to fluid and this film can attract grit orparticles that build-up over time which can interfere with fluid flowthrough the tubing or drip line and/or the individual emitters installedin the tubing or drip line.

Emitter 1810 includes a pressure compensating section or portion 1860that includes at least one stepped moveable baffle, such as a flipper ortooth member, that has an upper surface spaced apart from adjacent uppersurfaces (or the uppermost bonding surfaces of the emitter 1810) and/orfrom the inner surface of the tubing once the emitter 1810 is insertedin same. In a preferred form, the pressure compensation portion 1860will included at least a pair of stepped flippers 1847 a, 1847 b (alsoreferred to herein as baffles, baffle teeth or tooth members, flippers,etc.) and, in the form illustrated, the emitter 1810 contains a seriesof alternating stepped and moveable flippers 1847 a, 1847 b positionedon a trampoline portion 1861 of the emitter 1810 to form a pressurecompensating moveable baffle section 1862 with steps 1865 being locatedat the upper surface of the base or root of each baffle flipper/toothand the tooth tapering toward the tip or distal end of each tooth. Thepressure compensating section 1860 changes volume based on the pressurechange of the fluid in the tube. As the pressure in the tube increases,it raises the trampoline portion 1861 which moves the stepped baffles1847 a, 1847 b toward the inner surface of the tube. This reduces thevolume of the pressure compensating section 1860 (e.g., reduces thecross-sectional area of the flow passage at this portion of theemitter), which in turn, restricts the flow of fluid through thepressure compensating section 1860. The change reduces the flow incoordination with an increase of pressure within the system (e.g.,within the irrigation tubing and/or drip line network).

By lowering the upper surface of flippers 1847 a, 1847 b to create steps1865 (or creating a stepped configuration for these alternating teeth),emitter 1810 is capable of providing improved pressure compensationbecause bonding (e.g., partial bonding) of the upper surface of thestepped tooth is no longer a concern, and thus, the operation of thepressure compensation portion 1860 of the emitter 1810 will not beimpacted based on how much of the upper surface of the tooth is bondedto the inner surface of the irrigation tubing. Without this step orlowered surface at the base thereof, it has been discovered that somepressure compensation teeth (particularly at the base of those teeth)bond to the inner surface of the irrigation tubing more than otherpressure compensating teeth (from one tooth to another tooth in the sameemitter and/or from one emitter to another emitter) or in a non-uniformway amongst the pressure compensating teeth (from one tooth to anothertooth in the same emitter and/or from one emitter to another emitter)making it harder to form an emitter, emitters and/or drip line thatoperates consistently. As illustrated by the data in the followingchart, the stepped flipper configuration illustrated in FIGS. 19A-Cprovides a more consistent and repeatable pressure compensationcharacteristic from emitter to emitter and drip line to drip line, whichis important if such items are to be mass produced.

To illustrate this point, an emitter having a length (L) of nine hundredand one thousandths of an inch (0.901″), width (W) of two hundred thirtytwo thousandths of an inch (0.232″) and height (H) of ninety sixthousandths of an inch (0.096″) with a pressure reduction section 1850having a flow passage with a height or floor height (FH) of twenty-fivethousandths of an inch (0.025″) and flow passage width (FW) of twentythousandths of an inch (0.020″) and a pressure compensation trampolinearea of two hundred thousandths of an inch (0.200″) long by two hundredthirty two thousandths of an inch (0.232″) wide and stepped flippers1847 a, 1847 b with a gusset step of five thousandths of an inch(0.005″) down from the upper bonding surface of the adjacent orproximate emitter bonding surfaces and a floor thickness of fifteenthousandths of an inch (0.015″) was tested under various fluid linepressures and showed remarkably steady pressure compensation (e.g.,flowing steadily from seven pounds per square inch (7 psi) up to sixtypounds per square inch (60 psi)). The floor thickness of the flowpassages 1850, 1860 of the emitter 1810 is fifteen thousandths of aninch (0.015″), and it should be understood that floor height refers tothe distance from the upper surface of the floor to the top or bondingsurface of the emitter 1810 (or effectively the height of the flowpassage formed between the floor of the emitter and the inner surface ofthe tubing once the emitter is inserted therein). The inlet protrusion1832 has a length and width of one hundred four thousandths of an inch(0.104″) and a height of one hundred thousandths of an inch (0.100″).The results were as follows:

Flow Rates shown in (gph), Pressure shown in (psi) Pressure 5 7 10 15 2030 40 50 60 Avrg 0.166 0.187 0.191 0.188 0.187 0.185 0.184 0.184 0.189Flow Rate

In the embodiment illustrated, the stepped flippers or teeth taper froma height and width of twenty thousandths of an inch (0.020″) byforty-four thousandths of an inch (0.044″), respectively, at the base orroot of each tooth, all the way down to the floor of the flow passage ofFIGS. 19A-C (what also is referred to as a zero end taper or zero taperbecause the distal end of the tooth tapers to zero or merges into thefloor surface rather than truncating in a step). It should beunderstood, however, that in alternate embodiments, different shapes andsizes of teeth 1847 a, 1847 b may be used. For example, in another form,the pressure compensation portion 1860 may alternatively include steppedflippers or teeth 1847 a, 1847 b that taper down to a truncated tip atthe distal end of the tooth or flipper having a height of fivethousandths of an inch (0.005″) and a width of five thousandths of aninch (0.005″), similar to that shown with respect to FIGS. 18A-B. Thetruncation of the tip of the flippers or teeth may be in height (e.g.,leaving another step down in height to the flow passage floor surface)and/or in width. In the form illustrated in FIGS. 19A-C, the flippers orteeth have a zero taper, but the tips do not come to a point but ratherare truncated before reaching a pointed tip. In alternate forms,however, the tapering may taper both in height and width to a zerotaper. In practice, it has been found easier to mold a tip that istruncated in width than it is to mold a tip that tapers in width to zeroor toward zero. However, as mentioned herein, sharper surfaces form moreturbulence within the emitter and, thus, the geometry of the emitter maybe altered to provide sharper or duller surfaces in order to get theemitter to perform in a desired manner (e.g., using sharper surfaces toadd turbulence and create more pressure reduction throughout theemitter, use duller surfaces to reduce turbulence and create lesspressure reduction throughout the emitter). The rate of taper of theflippers or teeth may also be adjusted in order to get the emitter toperform as desired. Using a slower rate of taper to obtain an emitterwith a first performance characteristic and a greater rate of taper toobtain an emitter with a second performance characteristic differentthan the first. Any one of these modifications may be used with anynumber of the other modifications discussed herein in order to produceemitters with desired performance characteristics.

In addition to having an alternate pressure compensating portion 1860,emitter 1810 illustrates alternate outlet configuration 1840, whichincludes alternate outlet protrusions or stops 1841. In the formillustrated, the outlet protrusions 1841 are free floating or freestanding walls 1841 a, 1841 b, 1841 c capable of performing the functionof preventing or hindering the outlet 1840 from collapsing when thefluid pressure of supply line raises to a level sufficient fordeflecting the elastic floor of the emitter 1810, similar to the outletobstructions discussed above (e.g., 41, 941, etc.). Since theprotrusions 1841 a, 1841 b and 1841 c are freestanding, they do notconnect to the outer sidewalls of the outlet 1840 and operate moresimilar to the post protrusions 41 in FIGS. 1A-H in that they allowfluid to flow all the way around the protrusion 1841, which helps inpreventing or hindering grit/particulate buildup that could otherwiseform in the corners or ends of passages (also referred to as dead ends)like those illustrated in FIGS. 10A-12B. Thus, in the form illustratedin FIGS. 19A-C, the protrusions or walls 1841 a, 1841 b, 1841 c do notform dead ends in the outlet 1840 where debris can collect and build-upover time and ultimately negatively affect the operation or performanceof the emitter 1810.

Emitter 1810 further includes an alternate fastener 1849 for securingthe root growth inhibitor 1880 to the emitter 1810. In the formillustrated, fastener 1849 comprises a protrusion, such as a shoulder,lip or rib 1849, extending from at least one side wall of outlet 1840for securing a copper insert 1880 into position within outlet 1840. In apreferred form, the fastener 1849 includes at least two protrusions 1849a, 1849 b (FIG. 19C) for securing separate sides of the copper insert1880 to securely position the insert 1880 into a desired spot within theoutlet 1840. More particularly, protrusions 1849 a, 1849 b arepositioned on opposite sides of the outlet 1840 in order to secureopposite sides of the insert 1880 and are spaced above the floor of theoutlet 1840 an amount sufficient to secure the insert 1880 flush againstthe floor of the outlet 1840 so that debris or particulates cannotcollect under the insert 1880 or between the insert 1880 and the floorof outlet 1840. The insert 1880 will preferably be curved or arched totrack the radius of curvature of the floor of outlet 1840 to allow forsuch a flush mounting of the insert 1880.

During manufacture or assembly of emitter 1810, the insert 1880 willpreferably be press fit into the outlet 1840 by having the plate likeinsert 1880 inserted or disposed in the outlet 1840 and pressed passedthe protruding fastener 1849 to securely mount the insert 1880 intoposition within the outlet 1840. This may be accomplished manually ifdesired, however, in a preferred form, the insert 1880 will beautomatically inserted in this way via machinery such as a press. Insome embodiments, it may be desirable to apply another fastener such asan adhesive to either the floor of the outlet 1840 or the bottom surfaceof the insert 1880 to further bond or secure the insert to outlet 1840.In still other forms, another fastener may be used to connect the insert1880 to the outlet 1840 (either in lieu of or in addition to theshoulder protrusion 1849) such as a friction fit between the insertdefined openings 1880 a, 1880 b, 1880 c and their respective outlet wallmembers 1841 a, 1841 b, 1841 c.

One advantage of mechanical fasteners, such as shoulder protrusions 1849and/or the friction fit between the insert 1880 and outlet wall members1841, is that no chemicals are involved in the assembly of the emittercomponents, and thus, there is no need for concern as to how thosechemicals might react to materials, such as pesticides and fertilizers,that may be flushed through the emitter and drip line containing theemitter from time-to-time (e.g., no need for concern as to whether suchpesticides, fertilizers or other such chemicals could cause the adhesiveto become undone). Another advantage of such mechanical fasteners isthat there is no cure time involved in getting the insert 1880 fastenedto the outlet 1840 like there might otherwise be with adhesives and thelike or additional cost associated with the purchase and/or applicationof such adhesives. A mechanical fastener can be quickly and easilyfastened so that the emitter 1810 may immediately be inserted intotubing rather than requiring it to be allowed to cure or requiringadditional steps such as UV treatments to facilitate bonding, etc.Insertion machinery and methods of transporting and/or insertingemitters such as those described herein are disclosed in pending U.S.Provisional Patent Application No. 61/894,296, filed Oct. 22, 2013,which is incorporated herein by reference in its entirety.

In the form illustrated in FIGS. 19A-C, the floor of the outlet 1840 andthe flow passage of the pressure compensating portion 1860 and thepressure reduction portion 1850 are of a common depth (e.g., a commonfloor height as described above). Thus, when the insert 1880 isinstalled in the outlet 1840, the insert 1880 forms a step that raisesthe effective floor level of the outlet 1840 and, thus, reduces thefloor height in this portion of emitter 1810. However, in alternateembodiments, it may be understood that the floor of outlet 1840 could beset at a different level or position from that of the remainder of theflow passage, if desired. For example, the floor of outlet 1840 could besunken so that when the insert 1880 is installed in the outlet 1840 theupper surface of insert 1880 is level with the remainder of the flowpassage of the emitter so that a common floor height is providedthroughout the emitter 1810. This configuration may be desired in orderto prevent having a step in the flow passage where debris orparticulates could collect.

In yet other embodiments, different types of root growth inhibitingstructures may be desired. For example, as discussed above with respectto earlier embodiments, different positions may be desired for the rootgrowth inhibitor 1880. In some forms, it may be desired to position theinsert 1880 at the top of the emitter outlet 1840, just below the innersurface of the tubing to which the emitter is mounted and/or to have theinsert define an opening to the outlet of the tubing. In other forms, itmay be desirable to have the insert positioned intermediate the floor ofoutlet 1840 and inner surface of the tubing to which the emitter ismounted, such as midway between the two and only taking up a portion ofthe outlet so that fluid can flow around the insert and through to theoutlet of the tubing. In such configurations, the insert may have one ormore passages (e.g., perforations, holes, vias, etc.) or be sized toallow fluid to pass through the emitter and out the emitter outlet. Insome forms, a plurality of protruding shoulders may be positionedparallel to one another and spaced sufficiently apart from one anotherto allow for the insert 1880 to be sandwiched or retained between theparallel protrusions to retain the insert 1880 in the desired position.In addition and/or alternatively, the walls 1841 could be designed sothat they hold the insert 1880 at the desired position. For example,walls containing a wider base than respective insert openings could beused (e.g., a wall could gradually widened toward the base to provide apoint at which the insert cannot be further pressed into the outlet1840, a wall could be designed with a step or shoulder in an exteriorsurface thereof in order to place the insert at a desired position,etc.). In this way, the shoulder protrusion 1849 could alternatively belocated on the inner free-standing walls 1841 a, 1841 b and/or 1841 cinstead of being formed in the outer upstanding walls of the outlet 1840as illustrated in FIGS. 19A-C. In yet other forms, it may be desirableto have an insert that takes up less space within outlet 1840, such as anarrower or shorter plate that only extends about one of the outletprotrusion walls 1841 a, 1841 b, 1841 c. Similarly, a structure otherthan a plate could be used, such as a frame that surrounds a portion ofthe outer upstanding walls or inner upstanding walls of the outlet 1840.Although a solid plate type insert has been shown in FIGS. 19A-C, itshould be understood that in alternate forms the insert may be formed ofa mesh or screen type structure, or a matrix type structure that allowsfluid to flow through the emitter, the insert and out the emitteroutlet.

In yet other forms, it may be desirable to have the root growthinhibitor 1880 positioned elsewhere in the emitter or drip line besidesthe emitter outlet 1840. For example, in some forms, it may be desirableto have the root growth inhibitor 1880 connected to the drip line outletopening rather than the emitter 1810. As mentioned above, the rootgrowth inhibitor could be connected to the drip line tubing like acopper sleeve or rivet positioned at the outlet opening of the tubing.Pending International Patent Application No. PCT/US2013/046603, filedJun. 19, 2013, illustrates an alternate outlet tube that could beconnected to the drip line at the outlet and communicates with theemitter to control where fluid ultimately egresses from the emitter/dripline (e.g., at a location spaced from an outside surface of the dripline or supply tube so that the fluid does not simply run along theouter surface of the drip line/supply tube). In some forms, this outlettube and the root growth inhibitor could be combined into one structureto perform both tasks. For example, the outlet tube could be made out ofcopper so that it both directs fluid flowing from the emitter away fromthe outer surface of the drip line and inhibits roots from growingtoward the drip line and/or emitter. Thus, the disclosure ofInternational Patent Application No. PCT/US2013/046603 filed Jun. 19,2013 is incorporated herein by reference in its entirety, and it shouldbe understood that the outlet tube disclosed therein could be integratedwith root growth inhibitor 1880. It should be understood that any of thefeatures of the above embodiments may be used with one another to form avariety of different emitter embodiments. For example, in some forms, anemitter in accordance with the invention may include one or more of theinlet protrusion feature, root growth inhibitor feature, root growthinhibitor fastener feature, stepped baffle tooth or teeth feature, etc.

Additional emitter embodiments and features are illustrated in twosheets attached hereto as an Addendum. These sheets will not bedescribed in further detail herein due to their similarity to theembodiment of FIGS. 19A-C, other than to mention that the first sheetillustrates exemplary dimensions and a design for a non-zero end tapperstepped flipper (e.g., the tip of the flipper is truncated in height andwidth) and the second sheet illustrates exemplary dimensions and adesign for a zero end tapper stepped flipper (e.g., the flipper tapersto zero at its tip or distal end). In these embodiments, the outletportion has walls that are not freestanding, but rather connect to oneend of the outlet (e.g., one portion of the outer or peripheral wallthat forms the outlet).

Thus, it should be understood that various embodiments are contemplatedin accordance with the invention disclosed herein. For example, in oneform, an irrigation drip emitter for attachment to only acircumferential portion of an inner surface of an irrigation drip linetube carrying pressurized fluid is disclosed having a unitaryelastomeric body defining an inlet or inlet area, an outlet or outletarea and a flow channel connecting in fluid communication the inlet andoutlet or inlet area and outlet area. The flow channel defining apressure reduction portion and a pressure compensating portion having afirst volume at lower fluid pressure and a second volume smaller thanthe first volume at a higher fluid pressure to restrict flow through thechannel. Wherein the pressure compensating portion includes one or morestepped baffle teeth having a base, a tip, an upper surface extendingbetween the base and tip and a step along the upper surface, the stepspacing at least a portion of the upper surface of the one or morestepped baffle teeth from an inner surface of the irrigation drip linetube to facilitate movement of the one or more stepped baffle teeth.

In a preferred form, the one or more stepped baffle teeth will comprisea plurality of stepped tapered baffle teeth that alternate with oneanother and have a first set of stepped baffle teeth extending from afirst wall and tapering in a first direction and a second set of steppedbaffle teeth extending from a second wall located opposite the firstwall and tapering in a second direction opposite the first direction. Insome forms, the one or more stepped baffle teeth taper down to atruncated tip spaced slightly above the floor of the pressurecompensating portion of the emitter. In other forms, the one or morestepped baffle teeth are tapered down to a floor of the pressurecompensating portion of the emitter.

In a preferred form, the drip emitter will include at least onefreestanding wall positioned within the outlet or outlet area of theemitter such that fluid may flow entirely around exposed sides of the atleast one freestanding outlet wall. In addition, the emitter may alsoinclude a root growth inhibitor positioned in or proximate the outlet oroutlet area to deter roots from obstructing the flow of fluid from theemitter. In some forms, the emitter includes a fastener for securing theroot growth inhibitor in the outlet area of the emitter. In the formillustrated in FIGS. 19A-C, the fastener comprises at least oneprotrusion extending from at least one wall side surface located withinthe outlet or outlet area to secure the root growth inhibitor at theoutlet area. Emitters such as any of those described above may bepositioned within an irrigation drip line tube at predeterminedintervals and, preferably, regular or equally spaced intervals to form adrip line.

In other embodiments, irrigation drip emitters for attachment to only acircumferential portion of an inner surface of an irrigation drip linetube carrying pressurized fluid are disclosed having a unitaryelastomeric body defining an inlet area, outlet area and a flow channelconnecting in fluid communication the inlet and outlet areas. The flowchannel defining a pressure reduction portion and a pressurecompensating portion having a first volume or cross-sectional area atlower fluid pressure and a second volume or cross-sectional area smallerthan the first volume or cross-sectional area at higher fluid pressureto restrict flow through the channel. In a preferred form, the emitterwill have at least one freestanding outlet wall member positioned withinthe outlet area of the emitter such that fluid may flow entirely aroundexposed sides of the at least one freestanding outlet wall member.

In yet other forms, irrigation drip emitters for attachment to only acircumferential portion of an inner surface of an irrigation drip linetube carrying pressurized fluid are disclosed herein having a unitaryelastomeric body defining an inlet area, outlet area and a flow channelconnecting in fluid communication the inlet and outlet areas, with theflow channel defining a pressure reduction portion and a pressurecompensating portion having a first volume or cross-sectional area atlower fluid pressure and a second volume or cross-sectional area smallerthan the first volume at higher fluid pressure to restrict flow throughthe channel. The emitter further having a root growth inhibitorpositioned in or proximate the outlet area to deter roots fromobstructing the flow of fluid from the emitter and having a fastener forsecuring the root growth inhibitor in or proximate the outlet area ofthe emitter.

In still other forms, a non-cylindrical irrigation drip emitter forattachment to only a circumferential portion of an inner surface of anirrigation drip line tube carrying pressurized fluid is disclosed hereinhaving a unitary elastomeric body defining an inlet area, outlet areaand a flow channel therebetween connecting the inlet and outlet areas,with the flow channel defining a pressure reduction portion and apressure compensating portion having a first volume or cross-sectionalarea at lower fluid pressure and a volume or cross-sectional areasmaller than the first volume or cross-sectional area at higher fluidpressure to restrict flow through the channel. The pressure compensatingportion including at least one baffle tooth having a base, a tip and anupper surface extending between the base and tip, with the at least onebaffle tooth further having a stepped configuration wherein the base ofthe tooth is positioned at a height different from a proximate upperbonding surface of the emitter.

In one form, the at least one baffle tooth is tapered downward from thebase toward the tip and is moveable between a first lower pressureposition wherein the upper surface of the at least one baffle tooth isspaced apart from an inner surface of the irrigation drip line tube by afirst distance and which coincides with the first volume of the pressurecompensating portion and a second higher pressure position wherein theupper surface of the at least one baffle tooth is spaced apart from theinner surface of the irrigation drip line tube by a second distance lessthan the first distance and coincides with the second volume of thepressure compensating portion. In a preferred form, the at least onebaffle tooth is tapered down so that the tip of the tooth is flush witha floor of the pressure compensating portion of the emitter (e.g., azero-taper configuration). As with prior embodiments, the at least onebaffle tooth may comprise a plurality of stepped tapered baffle teetheach being moveable between the first lower pressure position and thesecond higher pressure position. Similarly, the plurality of steppedtapered baffle teeth may alternate with one another with a first set ofstepped baffle teeth extending from a first wall and tapering in a firstdirection and a second set of stepped baffle teeth extending from asecond wall located opposite the first wall and tapering in a seconddirection opposite the first direction.

In some forms, the non-cylindrical irrigation drip emitter may includeat least one freestanding outlet wall member positioned within theoutlet area of the emitter such that fluid may flow entirely aroundexposed sides of the at least one freestanding outlet wall member, andmay include a root growth inhibitor positioned in or proximate theoutlet area to deter roots from obstructing the flow of fluid from theemitter. A fastener for securing the root growth inhibitor in orproximate to the outlet area of the emitter may also be provided and/orused. For example, in the form illustrated in FIGS. 19A-C, the fastenercomprises at least one protruding shoulder extending from at least onewall side surface located within the outlet area that secures the rootgrowth inhibitor into the outlet area.

Although most of the embodiments discuss herein have specified a unitaryemitter body constructed of elastomeric material, it should beunderstood that any of the above embodiments may be provided in othermaterials if desired for particular applications. For example, in someforms it may be desired to provide non-pressure compensating versions ofthe above emitters. In such instances, the emitter bodies may be made ofmore rigid material, such as polyethylene or any material with a higherdurometer number, since movement of emitter body portions in response toincreases and decreases in fluid pressure in the drip line is notrequired in non-pressure compensating versions of the emitters.

It should also be understood that in alternate embodiments, the geometryor design of the emitter may be changed in order to get the emitter toperform in a desired manner for a particular application. For example,in some instances, an emitter with a higher flow rate may be desired,e.g., 1 gallon/hour (1 gph), instead of one with a lower flow rate,e.g., 0.2 gallon/hour (0.2 gph). In such cases, the emitter may bedesigned with fewer teeth in the pressure reduction (PR) region orportion of the emitter, fewer teeth in the pressure compensating (PC)region or portion of the emitter, with a flow channel with a greaterdepth (or greater floor height), with teeth and flow channel geometriesthat present less pressure reduction or greater fluid flow through theemitter (e.g., more rounded edges, less flat surfaces, softer angles,etc.), and the like. In addition, the entire emitter or just a portionof the emitter, such as the PC portion, could be made of a stiffermaterial with a higher durometer value so that the emitter chokes up orconstricts less to allow for a higher flow rate. Alternatively or inaddition, the emitter body or portions thereof (e.g., the trampoline ofthe PC portion) could be made thicker so that it is less flexible andchokes up or constricts less. As mentioned herein, the shape ofstructures may be made sharper or more duller to alter performance, therate of taper of the teeth in the PC or PR section may be altered tochange performance, etc.

In still other embodiments, the emitter could be designed to have one ormore receptacles for receiving different emitter portions (e.g.,portions with different geometries, such as different shapes, sizes,patterns, designs, etc., and/or portions that are made of differentmaterials so that the emitter may be provided in different flow rates orwith different optional features intended for a particular application).For example, in one form, the emitter may be designed with a receptaclefor receiving different PR portions to provide emitters with differentflow rates (e.g., 0.2 h, 0.5 gph, 1.0 gph, 2.0 gph, 5.0 gph, 7.0 h, 10.0h, 12.0 h, 18.0 gph, 24.0 gph, etc.). In one form, a lower flow rate PRportion insert may be provided with additional teeth, teeth with moreturbulence-inducing features or shapes, a smaller flow passagecross-section, etc. In another form, a higher flow rate PR portioninsert may be provided with fewer teeth, teeth with smoother features orshapes, a larger flow passage cross-section, etc. The different PRportion inserts may be inserted into the receptacle and optionallysecured thereto via any form of fastener, such as a friction fit, anadhesive, overmolding (e.g., having the insert molded over the remainderof the emitter body or having the emitter body molded over the insert,etc.). In a preferred form, the inserts will be friction fit into theemitter and emitters with common inserts placed into a vibratory drumfeeder for manufacturing drip line with common emitter flow rates asdisclosed in pending U.S. Provisional Patent Application No. 61/894,296,filed Oct. 22, 2013, which has been incorporated herein by reference inits entirety above.

In alternate forms, the emitter may be designed with a receptacle forreceiving different PC portions to provide emitters with differentproperties (e.g., flow rates, reaction times to variances in supply linefluid pressure, etc.). In one form, a lower flow rate PC portion and/ora faster reacting PC portion insert may be provided with additionalteeth, teeth with more turbulence-inducing features or shapes, smallerflow passage cross-section, made of a material or structure with ahigher durometer (e.g., with a higher durometer value), etc. In anotherform, a higher flow rate PC portion insert may be provided with fewerteeth, teeth with smoother features or shapes, a larger flow passagecross-section, made of a material or structure with a lower durometervalue, etc.

In still other forms, the emitter may be designed with a plurality ofreceptacles for receiving different emitter portions (e.g., emitterinlet portions, PR portions, PC portions and/or outlet portions, etc.).For example, in some forms the emitter may be provided with first andsecond receptacles for receiving PR portion and PC portion inserts,respectively. In FIGS. 20A-B an exemplary embodiment of an emitter withremovable, replaceable, or swappable PR and PC inserts is shown. Inkeeping with the above practice, items that are similar to thosediscussed above with respect to other embodiments are identified usingsimilar latter two-digit reference numerals, but having the prefix 19 todistinguish one embodiment from the others. Thus, in this embodiment,the emitter is referenced generally by reference numeral 1910 andincludes an emitter body 1920 made of a uniform elastomeric material anddefining an emitter inlet 1930 and outlet 1940 integral to the emitterbody 1920 with a flow passage extending between the inlet 1930 andoutlet 1940. In a preferred form, the flow passage includes a pressurereduction portion 1950 and a pressure compensating portion 1960. Unlikeprior embodiments, however, the emitter includes a pressure reduction(“PR”) insert 1950 a and a pressure compensating (“PC”) inset 1960 awhich are disposed within mating recesses defined by the emitter body1920. The mating recesses form sockets within which the PR insert 1950 aand PC insert 1960 a may be inserted or disposed prior to the emitterbeing connected to tubing.

Thus, with this configuration, emitter 1910 defines an open-facenon-cylindrical irrigation drip emitter for attachment to only acircumferential portion of an inner surface of an irrigation drip linetube carrying pressurized fluid. The emitter 1910 includes an emitterbody made of elastomeric material and defining at least one recess forreceiving an insert (e.g., at least one of the recess for receivinginsert 1950, the recess for receiving insert 1960, etc.). The emitter1910 further includes the insert (e.g., 1950 a, 1950 b, 1960 a, 1960 b,etc.) disposed within the recess defined by the emitter body 1920,together the emitter body and insert defining a flow passage between aninlet and outlet through which fluid may travel. In a preferred form,the recess defined by the emitter body 1920 is an open-faced sockethaving a first wall that extends about a majority of a side periphery ofthe insert and a second wall that traverses an opening defined by thefirst wall to close an end of the recess and define the open-facedsocket within which the insert is disposed, the insert being disposedwithin the open-faced socket by a sufficient amount to allow an uppersurface of the insert and an adjacent upper surface of the emitter bodyto be flush with one another so that the emitter assembly may be bondedto an inner surface of conduit without gaps forming between the uppersurfaces of the emitter body and insert and the inner surface ofconduit.

In this way, the emitter 1910 can be customized for a particular purpose(e.g., application, environment, flow rate, etc.) by allowing differenttypes of inserts to be installed for the various pressure reduction andpressure compensating portions. For example, the inserts 1950 a, 1960 amay be desired and used to form an emitter having a first fluid flowrate (e.g., 0.195 gallons per hour (GPH) or approximately 0.2 GPH).Whereas, alternate inserts 1950 b, 1960 b shown in broken line in FIG.20B may be desired and used to form an emitter having a second fluidflow rate different from the first fluid flow rate (e.g., 1 GPH). Theinserts 1950 a-b, 1960 a-b can do this by defining flow passages ofdifferent size, shape, pattern, or characteristic, by using materialswith different durometers (whether that be from the material chosenitself or from differences in the thickness or shape of the material,etc.), by using baffle teeth of different geometries (e.g., shapes,sizes, etc.) or with a different number of baffle teeth, etc. Forexample, one set of PC inserts 1860 a, 1860 b may be provided withstepped flippers or moveable baffle teeth that taper down to zero attheir distal end, whereas in other forms another set of PC inserts 1860b, 1860 a may be provided with flippers or moveable baffle teeth thatare not stepped at their base and that are truncated at their end ratherthan tapering down flush to the floor of the flow passage. In otherforms, one set of PR inserts 1850 a, 1850 b may be provided with a firstflow passage pattern and/or a first number of baffle teeth to achieve anemitter with a first characteristic, whereas in other forms another setof PR inserts 1850 b, 1850 a may be provided with a second flow passagepattern and/or a second number of baffle teeth (both different than therespective first flow passage pattern and number of baffle teeth) toachieve an emitter with a second characteristic different than the firstcharacteristic.

In a preferred form, the PR and PC inserts 1950, 1960 are made of thesame elastomeric material as the remainder of the emitter body 1920 andthe upper surfaces of the inserts 1950, 1960 have the same radius ofcurvature as the upper surfaces of the remainder of the emitter body1920 so that the assembled emitter 1910 (including the body 1920 andinserts 1950, 1960) can be bonded to the inner surface of tubing orconduit to produce a properly working emitter and drip line that doesnot leak and that drips fluid at the intended or desired flow rate. Byhaving a common radius of curvature the upper surfaces of the emitterbody 1920 and inserts 1950, 1960 will remain flush with one another sothat the emitter 1910 can be bonded to the inside surface of tubing orconduit without gaps that could result in leaks.

In other examples, the emitter may be provided with inlet and/or outletreceptacles for receiving inlet and/or outlet portion inserts (either inaddition to or in lieu of the PR and PC portion inserts). In yet otherforms, the inlet may be formed integral to the PR portion and thusremovable and insertable with the PR portion. It should be understoodthat the emitter may be provided with any one or more of suchreceptacles and inserts and that any of the insert or insert portionsdiscussed herein may optionally be secured to the emitter via a fasteneror the like as discussed above.

In addition to different geometries, different inserts may be used toallow a consumer to customize the emitter for a particular applicationor to provide options that can be added to or removed from the emitter.For example, in some applications such as steeply inclined or declinedlandscape (e.g., hilly or mountainous regions, etc.) inserts may beprovided with optional check valve designs used to prevent fluid fromflowing out of the emitters or drip line when not intended. In otherapplications, a protruding inlet that draws fluid from an inner portionof the supply or drip line (e.g., like that illustrated in FIGS. 10A-14Band 16A-19C) may be desired; whereas, in still other applications anon-protruding inlet may be desired to draw fluid from an outerperiphery or circumference of the supply line or dip line may be desired(e.g., like that shown in FIGS. 1A-9B and 15A-B). Thus, with thisconfiguration, emitters in accordance with the invention may becustomized for various applications, such as specific applicationsand/or based on specific attributes with respect to the environment theemitters will be used in.

Several different patterns for flow passages have been disclosed hereinand it should be understood that numerous other designs are contemplatedunder this disclosure and can be configured to get the emitters tooperate at the desired flow rate and/or with the desired grit toleranceor performance. In other forms, a different flow path may be utilized toreduce fluid pressure and/or compensate for fluctuations in fluid linepressure within the tube an emitter is mounted. An example of one suchalternate design is illustrated in FIGS. 21A-F and, in keeping withprior practice, will use the same latter two-digit reference numeral foritems similar to those discussed previously, but add the prefix 20 todistinguish this embodiment from others. Thus, in FIGS. 21A-F, theemitter is referenced generally as reference numeral 2010 and includes aunitary body of elastomeric material 2020 that forms an inlet 2030, anoutlet 2040 and a flow path extending between the inlet and the outletincluding a pressure reduction (“PR”) portion 2050 and a pressurecompensating (“PC”) portion 2060.

In a preferred form, emitter 2010 is a discrete, single pieceelastomeric emitter intended to be attached to only a portion of aninner circumference of an inner surface of an irrigation drip line tubelike tube 70 in FIG. 1A and tube 970 in FIG. 10E. The discreteelastomeric emitter body 2020 integrally defines the inlet 2030 on afirst side of the body for receiving pressurized fluid from a fluidsupply source, the outlet 2040 on a second side of the body fordischarging the fluid from the body, with a flow channel extendingbetween the inlet 2030 and outlet 2040 and including the above-mentionedPR portion 2050 and PC portion 2060. The emitter further defines atleast one internal wall that is movable to adjust the pressure and/orflow rate of the fluid received at the inlet and discharged through theoutlet and a perimeter wall forming at least a portion of an exterior ofthe emitter body and forming at least a portion of a curved uppersurface of the emitter body 2020 that is shaped to correspond to aninterior radius of curvature of the portion of the inner circumferenceof the inner surface of the irrigation drip line tube to which theemitter body is to be mounted. In some forms, the internal wall islocated in the PC portion 2060 of the emitter 2010 and moves along withother portions of the PC portion 2060 of the emitter (e.g., the floor ofthe PC portion) in response to a change in pressure of the pressurizedfluid traveling through the tube from the fluid supply source. Apreferred dripline is then formed by bonding the emitter 2010 at regularintervals to the inner surface of the tube and then forming an outletopening through the tube over or aligned with the outlet 2040 so thatfluid can flow from the tube.

As with prior embodiments discussed above, at least a portion of theemitter body 2010 further defines a generally planar floor in the outlet2040 and an obstruction, such as posts or walls 2041 a, 2041 b and 2041c, that extends upward from the floor for preventing the outlet 2040from collapsing in response to increases in pressure of the pressurizedfluid within the tube. The obstructions 2041 a-c could be any shape, butpreferably will be posts or walls and will include a curved uppersurface that corresponds in height and shape to the curved upper surfaceof the emitter body 2020. In the form illustrated, emitter 2010 furtherincludes an inlet protrusion 2032 that extends from the emitter body andaway from the emitter proximate the inlet 2030 to draw fluid from alocation closer to the center of the tube which tends to have fluid withless debris than the fluid traveling near the inner surface of the tube.

Unlike prior embodiments, however, emitter 2010 has a multi-stage PRportion 2050 including a serpentine shaped tortuous flow passage havinga first portion 2050 a containing baffles and a second portion 2050 bwithout baffles. The portion with baffles 2050 a is positioned proximatethe inlet 2030 and, in particular, downstream of the inlet 2030. Theflow path then transitions from the portion with baffles 2050 a to thePR portion without baffles 2050 b, which in the form illustratedcomprises smooth walls or a buffer zone devoid of baffles as the flowpath transitions from the portion with baffles to the PC portion 2060.The upper surfaces of both PR portions 2050 a and 2050 b are of the sameheight (or of equal or constant height) and preferably track the radiusof curvature of the upper surfaces of the emitter 2010, whichcorresponds to the radius of curvature of the inner tube surface towhich the emitter 2010 is ultimately bonded in order to provide a sealedflow passage between the emitter 2010 and tube.

As illustrated in FIGS. 20A-E, the tortuous flow passage of emitter 2010is defined by a plurality of baffles and is laid out in a windingserpentine path. The plurality of baffles comprise baffles of constantheight (e.g., those in PR portion 2050 a) and baffles of tapering height(e.g., baffles 2067 a, 2067 b in PC portion 2060). The baffles ofconstant height are positioned in the first portion 2050 a of pressurereduction portion 2050 of the flow passage and the baffles of taperingheight 2067 a, 2067 b are positioned in the pressure compensationportion 2060 of the flow passage. More particularly, the baffles ofconstant height are positioned downstream of the inlet 2030 and thebaffles of tapering height 2067 a, 2067 b are positioned downstream ofthe baffles of constant height in PR portion 2050 a and upstream of theoutlet 2040. The second portion 2050 b of PR portion 2050 forms aserpentine flow passage and buffer zone between the baffles of constantheight and the baffles of tapering height free or devoid of any baffles.

The flow passage of emitter 2010 transitions from the PR portion withoutbaffles 2050 b to the PC portion 2060. The PC portion 2060 furtherincludes one or more movable baffles, such as tapered baffles 2067 a and2067 b. In a preferred form and as best illustrated in FIGS. 21D and21E, the tapered baffles 2067 a, 2067 b are stepped baffles with theupper baffle surface being stepped down from the upper surface of theadjacent wall structure from which the baffle extends. The steps 2065 aand 2065 b are located at the base of the baffles and the baffles tapertoward the distal end of the baffles and toward the floor of the flowpassage. In some forms, the baffles taper all the way down to the floorof the flow passage (also known as a zero taper), while in other formsthey have less of a taper such that the distal end still protrudes upfrom or forms a step with the floor of the PC portion 2060.

Thus, emitter 2010 forms an irrigation drip emitter for attachment toonly a portion of an inner circumference of an inner surface of anirrigation drip line tube having a discrete elastomeric emitter body2020 integrally defining an inlet 2030 on a first side of the body 2020for receiving pressurized fluid from a fluid supply source, an outlet2040 on a second side of the body for discharging the fluid from thebody, a flow channel extending between the inlet 2020 and outlet 2030for reducing a pressure and flow of fluid received at the inlet 2030 anddischarged through the outlet 2040. The flow channel defined by at leastone inner wall and further including a pressure compensating portion2060 having a plurality of baffles 2067 a, 2067 b extending from one ormore side walls that border the pressure compensating portion 2060, withat least two baffles extending from the one or more side walls thatborder the pressure compensating portion 2060 and separating thepressure compensating portion 2060 into an upstream portion 2060 a and adownstream portion 2060 b with the upstream portion 2060 a having alarger area and volume than the downstream portion 2060 b to ensuregreater pressure is exerted on the upstream portion than the downstreamportion to assist in flushing the emitter 2010 of grit, as explainedfurther below.

More particularly, when the emitter 2010 is bonded to the inside of adrip tube and fluid pressure within the drip tube increases, pressure isexerted on the exterior of the floor 2061 of the pressure compensatingportion 2060 thereby causing the floor 2061 and at least two baffles2067 a, 2067 b to move toward the tube surface to which the emitter 2010is bonded. This reduces the cross-section of the flow channel 2050, 2060(or flow passage opening) defined by the emitter 2010 and tube to whichit is bonded and allows the emitter 2010 to compensate for the fluidpressure increase by making a corresponding decrease in flow passagecross-section to control the amount of fluid flowing therethrough. Also,the distal ends of the at least two baffles 2067 a, 2067 b form a pinchpoint or constriction 2060 c through which the fluid must travel inorder to pass through the flow passage and on to the outlet 2040 of theemitter. In the form illustrated, baffles 2067 a, 2067 b extend out fromseparate side walls that border the pressure compensating portion 2060toward one another and in an upstream direction, with one of the atleast two baffles 2067 a, 2067 b extending further than the other inorder to create another pressure reducing turn for fluid travelingthrough the flow passage. In the form illustrated, the baffles 2067 a,2067 b angle upstream and baffle 2067 a extends further upstream thanbaffle 2067 b in order to create an additional turn for the fluidtraveling through the pinch point 2060 c created by the ends of thebaffles 2067 a, 2067 b.

Emitter 2010 includes a perimeter wall forming at least a portion of anexterior of the emitter body 2020 and forms a curved upper surface ofthe emitter body that is shaped to correspond to the inner radius ofcurvature of the tube to which the emitter is bonded (e.g., to aninterior radius of curvature of the portion of the inner circumferenceof the inner surface of the irrigation drip line tube to which theemitter body is to be mounted). The step 2065 a, 2065 b in the at leasttwo baffles 2067 a, 2067 b positions the upper surface of the baffles2067 a, 2067 b below the upper surface of the remainder of the emitteror at least the perimeter wall of the emitter 2010. The steps 2065 a,2065 b allow fluid to flow over at least some portions of the baffles2067 a, 2067 b at all times, but primarily allow the baffles 2067 a,2067 b to move more consistently from emitter to emitter and, thus,allow the emitters to be manufactured with more repeatable accuracy(again emitter to emitter). In turn, this means that emitters with moreconsistent performance from emitter to emitter will yield dripline withmore consistent performance (dripline to dripline). In a preferredprocess, a plurality of emitters of the type disclosed herein (bothabove and below) will be bonded to the inner surface of drip linetubing, at regular intervals, as the tubing is extruded and then anopening (e.g., hole, slit, etc.) will be formed in the tubing over theemitter outlet 2040 in order to form operational drip line tubing thatallows fluid flowing through the tubing to flow into the emitter inlet2030, through the flow passage 2050, 2060 to the emitter outlet 2040 andthen out through the opening (e.g., hole, slit, etc.) formed in the dripline tubing.

The emitter 2010 preferably defines a generally planar floor in theoutlet 2040 and an obstruction, such as walls 2041 a-c, extending upwardfrom the floor for preventing the outlet 2040 from collapsing inresponse to increases in pressure of the pressurized fluid travelingthrough the drip line tubing. In the form illustrated, the obstructioncomprises a first wall 2041 b extending from a side wall defining aportion of the outlet 2040 and extending into a center of the outlet2040, and two additional free standing walls 2041 a, 2041 c positionedon opposite sides of the first wall 2040 b and spaced from any sidewalls defining the outlet 2040 so as to prevent creating dead ends orzones where grit/debris can become trapped within the emitter. Theupstanding edges of the walls can be curved. These features help theemitter 2010 flush grit that may be encountered during use of theemitter 2010 in normal applications or uses.

An inlet protrusion 2032 that extends away from the emitter body 2020 todraw fluid from a position closer to the center of the irrigation dripline tube instead of from an outer periphery of the tube is alsoillustrated and helps reduce the amount of grit introduced into theemitter 2010. In some forms, the inlet protrusion 2032 may define achannel or channels on a distal end thereof, such as the channels 1332a-f illustrated in FIGS. 14A-B above, which are sized to deflect foreignmaterial (e.g., grit/debris) from obstructing the inlet or entering theemitter body 2010 with the channel being defined by an exterior surfaceof the inlet protrusion, as has been discussed in alternate embodimentsdisclosed herein. However, in the form illustrated in FIGS. 21A-E, suchan inlet protrusion channel or filter is not needed in all forms of theemitter given the grit flushing ability of emitter 2010.

Thus, when inserted into tubing, the emitter 2010 and tubing formirrigation dripline having a tube with an inside surface, at least onediscrete elastomeric emitter body 2010 attached to the inside surface ofthe tube and integrally defining: an inlet on a first side of the body2020 for receiving pressurized fluid from the tube; a pressure reducingflow channel 2050 extending from the inlet 2030 for reducing a pressureand flow of fluid received at the inlet 2030; and a pressurecompensating chamber 2060 configured to receive fluid from the pressurereducing flow channel 2050. The PC chamber 2060 is defined by moveablefloor 2061 and at least two opposing side walls and the inside surfaceof the tubing to which the emitter is connected. The chamber 2060preferably includes at least two teeth or baffles 2067 a, 2067 b, withone extending from each of the at least two opposing side walls toward acenter region of the chamber 2060. The at least two teeth 2067 a, 2067 bdividing the chamber 2060 into at least an upstream portion 2060 a and adownstream portion 2060 b, the upstream portion 2060 a being larger thanthe downstream portion 2060 b, and the two teeth 2067 a, 2067 b beingmoveable toward and away from the inside surface of the tube an amountdepending on the pressure of the fluid in the tube to adjust thepressure and flow of the fluid received from the pressure reducing flowchannel 2050. In the form illustrated, the teeth 2067 a, 2067 boriginate from a position in the chamber closer to the outlet 2040 thanthe PR flow passage 2050 and angle upstream toward the center region ofthe PC chamber 2060.

In a preferred form, the pressure reducing flow channel 2050 has a flooror bottom with a first thickness and the moveable floor 2061 of pressurecompensation chamber 2060 has a second thickness, the second thicknessbeing less than the first thickness to allow sufficient movement of themoveable floor 2061 relative to the remainder of the emitter and/or thetubing for providing a predetermined range of movement for the moveablefloor. More particular, in the form illustrated, the exterior of emitterbody 2020 is recessed (e.g., into the side from which inlet protrusion2132 extends) to reduce thickness of the movable floor 2061 as comparedto the remainder of the emitter 2010 (and in particular the floor of thepressure reduction flow channel 2050 and outlet 2040). This allows themoveable floor 2061 to operate like a trampoline and more easily moveteeth or baffles 2067 a, 2067 b and/or makes the emitter 2010 moreeasily reproducible with consistent performance characteristics. Across-sectional view exemplifying this floor thickness is shown and willbe discussed further with respect to FIG. 24E. Although the floor of theremainder of the flow passage (e.g., pressure reduction portion) and theoutlet illustrated in that cross-sectional view is illustrated as ratherthick, in alternate embodiments moveable floors of different thicknessmay be used, such as thinner floors like the one illustrated in FIG. 19B(see floor 1861).

In operation, the teeth 2067 a, 2067 b move toward the wall of the dripline tube to which the emitter is connected as pressure of the supplyfluid in the tube increases. This causes the passage over the teeth 2067a, 2067 b to become smaller and, therefore, restricts flow past theteeth 2067 a, 2067 b. As pressure of the supply fluid in the tubedecreases, the teeth 2067 a, 2067 b move away from the wall of the dripline tube to which the emitter is connected (e.g., away from the innertube surface) to allow more fluid to flow through the emitter (e.g.,over teeth 2067 a, 2067 b). In addition, one tooth extends slightlyfurther upstream than the other in order to introduce yet another turnin the flow passage as the teeth are constricted for further pressurereduction. In a preferred form, the emitter 2010 is configured toproduce drips of fluid at a 0.4 gallon per hour (0.4 gph) flow rate.

As mentioned, there is potential for obstructions, such as grit, toaffect or even clog the emitter 2010, especially at the teeth 2067 a,2067 b in the pressure compensation portion or chamber 2060. Forinstance, as the supply line fluid pressure increases, the teeth 2067 a,2067 b move toward the inner surface of the tube creating a constrictionalong the top of the teeth 2067 a, 2067 b (as described above). Therealso is a constriction between the distal ends of the teeth 2067 a, 2067b. As these constrictions form, the risk of grit clogging the edges ofteeth 2067 a, 2067 b increases as does the risk for complete blockage orclogging of the emitter 2010. Once the blockage or clogging affects theflow too much, pressure will build up on the upstream side 2060 a ofteeth 2067 a, 2067 b. Since the area of the floor 2061 on the upstreamside 2060 a of the teeth and the volume of that upstream portion of thePC chamber is greater than the area of the floor on the downstream side2060 b and the volume of that downstream portion of the PCT chamber, thepressure will cause the floor 2061 to move away from the inside surfaceof the tube. This will cause the teeth 2067 a, 2067 b to also move awayfrom the inner surface of the tube, which permits the debris forming theclog or blockage to be flushed from the pressure regulating chamber 2060over the teeth 2067 a, 2067 b. Once the blockage or clog is flushedsufficiently, the pressure build-up on the upstream side 2060 a of theteeth 2067 a, 2067 b will drop and the pressure compensating chamber2060 will resume its normal pressure compensating function.

In a preferred form, the walls or teeth 2067 a, 2067 b are angled orpointed upstream on an intersecting course from the walls from whichthey extend within the pressure compensating chamber 2060 in order toprevent the teeth 2067 a, 2067 b from forming a funnel that could getclogged more easily and frequently. This is counter-intuitive as onewould normally think to have the baffles aligned or funnel downstream inorder to assist with fluid flow and, in particular, the flushing ofgrit/debris. It also is counter-intuitive in that the design usedappears to form dead ends or zones at the upstream side of the base ofeach tooth where the tooth connects to the side wall from which itextends. However, applicant has found that by using this configurationthe volume and area of the upstream side 2060 a of the pressurecompensation portion 2060 is capable of being made larger than thevolume and area of the downstream side 2060 b and allows the emitter2010 to flush grit, debris or obstructions more effectively in themanner discussed above. In the form shown, the tips of teeth 2067 a,2067 b do not overlap with one another and include a gap (e.g.,0.005±0.002) at the pinch point 2060 c in order to help flushgrit/debris. Further dimensions regarding an exemplary PC chamber willbe discussed in more detail below with respect to FIGS. 24A-F.

Another embodiment of an emitter in accordance with the invention isillustrated in FIGS. 22A-E and in keeping with prior practice, thefollowing will use the same latter two-digit reference numeral todescribe similar items, but use the prefix 21 to distinguish thisembodiment from others. Thus, in these illustrations, the emitter isreferred to general as 2110 and integrally defines an inlet 2130, anoutlet 2140 and a passage made up of a pressure reduction (PR) portion2150 and a pressure compensation portion (PC) portion 2160 all formedfrom a uniform elastomeric material. Unlike the embodiment of FIGS.21A-E, emitter 2110 of FIGS. 22A-E has a consistent pressure reductionpassage 2150 that serpentines back and forth, but in a less aggressivemanner as that used with emitter 2010. The emitter 2110 further includesin inlet protrusion 2132 defined by an elongated protrusion orprojection extending from one end of the emitter body 2120 and outletobstructions, such as walls 2141 a-c, for preventing the outlet 2140from collapsing under pressure when pressure increases in the lumen ofthe tubing to which the emitter 2110 is mounted.

The PC portion 2160 is similar to that of the PC portion 2060 of emitter2010. The PC portion 2160 includes moveable floor 2161 and taperedbaffles 2167 a, 2167 b which extend from side walls that define the PCportion 2160. The baffles 2167 a, 2167 b are preferably angled upstreamtoward one another and the center of the PC portion 2160, with onebaffle 2167 a extending further upstream than the other baffle 2167 b inorder to provide an additional pressure reducing turn that fluid has tomake when the movable floor 2161 is moved toward the inner surface ofthe tube to which the emitter 2110 is mounted as fluid pressureconditions within the tube increase. Like emitter 2010, the distal endsof baffles or teeth 2167 a, 2167 b form a pinch point or constriction2160 c through which fluid traveling through the emitter 2110 has topass. The baffles or teeth 2167 a, 2167 b further separate the PCportion 2160 into an upstream portion 2160 a and a downstream portion2160 b, and the upstream portion 2160 a has an area and volume greaterthan the area and volume of the downstream portion 2160 b so that morepressure is exerted on the upstream portion 2160 a of the PC portion2160 so as to assist with flushing grit through emitter 2110.

In operation, the teeth 2167 a, 2167 b move toward the wall of the dripline tube to which the emitter 2110 is connected as pressure of thesupply fluid in the tube increases. This causes the passage over theteeth 2167 a, 2167 b to become smaller and, therefore, restricts flowpast the teeth 2167 a, 2167 b. As pressure of the supply fluid in thetube decreases, the teeth 2167 a, 2167 b move away from the wall of thedrip line tube to which the emitter is connected (e.g., away from theinner tube surface) to allow more fluid to flow through the emitter(e.g., over teeth 2167 a, 2167 b). In addition, one tooth extendsslightly further upstream than the other in order to introduce yetanother turn in the flow passage as the teeth are constricted forfurther pressure reduction. In the form illustrated, the emitter 2110 isconfigured to drip fluid at a flow rate of approximately 0.6 gallons perhour (0.6 gph).

As mentioned previously, there is potential for obstructions, such asgrit, to affect or even clog the emitter 2110, especially at the teeth2167 a, 2167 b in the pressure compensation portion or chamber 2160. Forinstance, as the supply line fluid pressure increases, the teeth 2167 a,2167 b move toward the inner surface of the tube creating a constrictionalong the top of the teeth 2167 a, 2167 b (as described above). Therealso is a constriction 2160 c between the distal ends of the teeth 2167a, 2167 b. As these constrictions form, the risk of grit clogging at theteeth 2167 a, 2167 b increases as does the risk for complete blockage orclogging of the emitter 2110. Once the blockage or clogging affects theflow too much, pressure will build up on the upstream side 2160 a ofteeth 2167 a, 2167 b. Since the area of the floor 2161 and correspondingvolume on the upstream side 2160 a of the teeth is greater than that ofthe downstream side 2160 b, the pressure will cause the floor 2161 tomove away from the inside surface of the tube. This will cause the teeth2167 a, 2167 b to also move away, which permits the debris forming theclog or blockage to be flushed from the pressure regulating chamber2160. Once the blockage or clog is flushed sufficiently, the pressurebuild-up on the upstream side 2160 a of the teeth 2167 a, 2167 b willdrop and the pressure compensating chamber 2160 will resume its normalpressure compensating function.

In a preferred form, the walls or teeth 2167 a, 2167 b are angled orpointed upstream on an intersecting course from the walls from whichthey extend within the pressure compensating chamber 2160 in order toprevent the teeth 2167 a, 2167 b from forming a funnel that could getclogged more easily and frequently. This is counter-intuitive as onewould normally have the teeth extend directly toward one another, orstaggered but extending in opposing directions, or angled downstream tocreate a pressure reduction, but not a clogging point. It also iscounter-intuitive in that the design used appears to form dead ends orzones at the upstream side of the base of each tooth where the toothconnects to the side wall from which it extends and could collect debristhat ultimately could clog the emitter. However, applicant has foundthat by using this configuration the areas at the base of the teethflush better. Further, this configuration assists to make the area andvolume of the upstream side 2160 a of the pressure compensation portion2160 larger than the area and volume of the downstream side 2160 b andallows the emitter 2110 to flush grit, debris or obstructions in themanner discussed above. In the form shown, the tips of teeth 2167 a,2167 b do not overlap with one another and include a gap (e.g.,0.005±0.002) at pinch point 2160 c in order to help flush grit.

Yet another emitter design in accordance with the invention isillustrated in FIGS. 23A-E and, in keeping with prior practice regardinguse of similar numbering on similar items, is referenced generally byreference numeral 2210. In the form illustrated, emitter 2210 forms adiscrete, single piece, elastomeric emitter body 2220 intended to bebonded to a portion of an inner surface of a drip line tube andintegrally forming an inlet 2230, an outlet 2240 and a flow passageextending between the inlet 2230 and outlet 2240 made up of a pressurereduction (PR) portion 2250 and a pressure compensation (PC) portion2260. PR portion 2250 travels in a less aggressive serpentine manner(even less aggressively than the PR portion 2150 of emitter 2110) andhas smooth walls over a portion of its distance (rather than teethextending from the walls over the length of the PR portion). Incomparison, the PR portion 2050 causes the most pressure reduction, thePR portion 2150 causes the second most pressure reduction, and this PRportion 2250 causes the least pressure reduction of the three PRportions disclosed in the embodiments of FIGS. 21A-23F. The emitter 2210further includes an inlet protrusion 2232 to draw cleaner (or lessgritty) water from the center of the drip line and includes outletobstructions or supports, such as walls 2241 a-c, to prevent the outlet2240 from collapsing under increased fluid line pressure.

Like the emitter embodiments of FIGS. 21A-E and 22A-E, emitter 2210 ofFIGS. 23A-E further includes a moveable floor 2261. The exterior of theemitter body 2220 is recessed to reduce the thickness of the floor 2261and allow the floor 2261 to move more easily and responsively to changesin fluid pressure within the tube to which the emitter is mounted. Thus,floor 2261 operates in a trampoline-like manner to move tapered bafflesor walls 2267 a, 2267 b between a first, low fluid pressure position anda second, high fluid pressure position. The low and high fluid pressurereferring to the fluid pressure of the fluid within the lumen of thedrip line tube in which the emitter 2210 is mounted or affixed. Thetapered baffles or walls 2267 a, 2267 b form a pinch point orconstriction 2260 c through which fluid must travel. The constrictionfurther forms when the baffles 2267 a, 2267 b move toward their highfluid pressure position. That is, as they move toward the inner surfaceof the tube that the emitter is connected to as fluid pressure increasesin the tube (i.e., when the floor 2161 elevates), which translates to aflow passage having a smaller cross-sectional area than the flow passagecross-sectional area when the baffles 2267 a, 2267 b are in their lowfluid pressure position (i.e., when the floor 2161 is in its normallybiased position). Baffle walls 2267 a, 2267 b extend from side wallsdefining PC portion 2260 and are angled upstream so as to divide the PCportion into a PC portion having an upstream portion 2260 a and adownstream portion 2260 b, with the upstream portion 2260 a having agreater area and volume than the downstream portion 2260 b so that morepressure is exerted against the upstream portion 2260 a to help flushthe emitter 2210 of grit.

In operation, the teeth 2267 a, 2267 b move toward the wall of the dripline tube to which the emitter 2210 is connected as pressure of thesupply fluid in the tube increases. This causes the passage over theteeth 2267 a, 2267 b to become smaller and, therefore, restricts flowpast the teeth 2267 a, 2267 b. As pressure of the supply fluid in thetube decreases, the teeth 2267 a, 2267 b move away from the wall of thedrip line tube to which the emitter is connected (e.g., away from theinner tube surface) to allow more fluid to flow through the emitter(e.g., over teeth 2267 a, 2267 b). In addition, one tooth extendsslightly further upstream than the other in order to introduce yetanother turn in the flow passage as the teeth are constricted forfurther pressure reduction. In the form illustrated, the emitter 2210 isconfigured to drip fluid at a flow rate of approximately 0.9 gallons perhour (0.9 gph).

As mentioned previously, there is potential for obstructions, such asgrit, to affect or even clog the emitter 2210, especially at the teeth2267 a, 2267 b in the pressure compensation portion or chamber 2260. Forinstance, as the supply line fluid pressure increases, the teeth 2267 a,2267 b move toward the inner surface of the tube creating a constrictionalong the top of the teeth 2267 a, 2267 b (as described above). Therealso is a constriction between the distal ends of the teeth 2267 a, 2267b. As these constrictions form, the risk of grit clogging the edges ofteeth 2267 a, 2267 b increases as does the risk for complete blockage orclogging of the emitter 2210. Once the blockage or clogging affects theflow too much, pressure will build up on the upstream side 2260 a ofteeth 2267 a, 2267 b. Since the area of the floor 2261 on the upstreamside 2260 a of the teeth is greater than the area of the floor on thedownstream side 2260 b, the volume of the upstream portion is largerthan the volume of the downstream portion and pressure will cause thefloor 2261 to move away from the inside surface of the tube. This willcause the teeth 2267 a, 2267 b to also move away, which permits thedebris forming the clog or blockage to be flushed from the pressureregulating chamber 2260. Once the blockage or clog is flushedsufficiently, the pressure build-up on the upstream side 2260 a of theteeth 2267 a, 2267 b will drop and the pressure compensating chamber2260 will resume its normal pressure compensating function.

In a preferred form, the walls or teeth 2267 a, 2267 b are angled orpointed upstream on an intersecting course from the walls from whichthey extend within the pressure compensating chamber 2260 in order toprevent the teeth 2267 a, 2267 b from forming a funnel that could getclogged more easily and frequently. This is counter-intuitive as onewould normally think to have the baffles aligned or funnel downstream toassist operation of the emitter and the emitter's ability to process orhandle debris/grit. It also is counter-intuitive in that the design usedappears to form dead ends or zones at the upstream side of the base ofeach tooth where the tooth connects to the side wall from which itextends. However, applicant has found that by using this configurationthe area and volume of the upstream side 2260 a of the pressurecompensation portion 2260 is capable of being made larger than that ofthe downstream side 2260 b and allows the emitter 2210 to flush grit orobstructions in the manner discussed above. In the form shown, the tipsof teeth 2267 a, 2267 b do not overlap with one another and include agap (e.g., 0.005±0.002) in order to help flush grit, and the teeth 2267a, 2267 b form an acute angle with the respective walls they extend fromon their upstream side and an obtuse angle with the respective wallsthey extend from on their downstream side.

Yet another elastomeric emitter embodiment is illustrated in FIGS.24A-F. In keeping with prior practice, items that are similar to thosediscussed above will use the same latter two digit reference numeral butadd the prefix “23”. Thus, the emitter is referred to generally byreference numeral 2310 and includes an emitter body 2320 made of asingle piece construction and integrally forming an inlet 2330, outlet2340 and an internal flow passage having a pressure reduction (PR)portion 2350 and a pressure compensating (PC) portion 2360. Like theemitter of FIGS. 21, 22 and 23, the emitter of FIGS. 24A-F includes aninlet protrusion 2332 that forms a perimeter wall extending about theinlet opening 2330 and helps draw fluid from a position closer to thecenter of the conduit or tubing within which the emitter is mounted. ThePC portion 2360 has two tapered baffle teeth 2367 a, 2367 b that dividesthe PC portion 2360 into an upstream portion 2361 a and a downstreamportion 2361 b.

In the form illustrated, the outer boundary or side walls that definethe PC portion 2360 have a length of two hundred thousandths of an inchplus or minus five thousandths of an inch (0.200″±0.005″) and a width oftwo hundred thirty two thousandths of an inch plus or minus fivethousandths of an inch (0.232″±0.005″), with the height of the PCportion (floor height) being twenty five thousandths of an inch plus orminus five thousandths of an inch (0.025″±0.005″). The height of the PCportion is slightly smaller than the height of the PR portion which isthirty hundredths of an inch plus or minus fifteen thousandths of aninch (0.32″±0.015″). This further reduces the cross-section of the flowpassage from inlet 2330 to outlet 2340 and helps with pressurereduction. The teeth 2367 a, 2367 b have a step (e.g., gusset step) offive thousandths of an inch plus or minus two thousandths of an inch(0.005″±0.002″) and taper down to a distal end height of fifteenthousandths of an inch plus or minus two thousandths of an inch(0.015″±0.002″). In order to ensure the PC portion 2360 provides enoughmovement to compensate for fluid line pressure increases in the innerlumen of the conduit containing the emitter 2310, the floor of the PCportion has a thickness or height of thirty thousandths of an inch plusor minus two thousandths of an inch (0.030″±0.002″). Thus, the teeth2367 a, 2367 b act as stepped flipper teeth that move up and down withchanges in fluid line pressure to compensate for such changes.

In the form illustrated in FIGS. 24A-F, the teeth 2367 a, 2367 b extendfrom their respective side walls at an angle α and an angle β,respectively. In a preferred form, angle α of tooth or stepped flipper2367 a is fifty-two degrees (α=52°), however, in alternate forms thisangle may range between forty-seven degrees to fifty-seven degrees (α:47°-57°) (which is 52°±5°). In still other forms, angle α may rangebetween forty-two degrees and sixty-two degrees (α: 42°-62°) (or52°±10°). In the form illustrated, the angle β that tooth or steppedflipper 2367 b extends from the side wall of the PC portion is fifty-twodegrees (α=60°), however, in alternate forms this angle may rangebetween fifty-five degrees to sixty-five degrees (β: 55°-65°) (which is60°±5°). In still other forms, angle β may range between fifty degreesand seventy degrees (β: 50°-70°) (or 60°±) 10°. These angles, combinedwith the length of the teeth or flippers 2367 a, 2367 b, allow the firsttooth or stepped flipper 2367 a to extend further upstream than secondtooth or stepped flipper 2367 b in order to position the opening orpinch point 2360 c in the middle of the PC portion 2360. In the formillustrated in FIGS. 24A-F, the opening between the teeth 2367 a, 2367 bis positioned in the middle of the PC pocket 2360 to obtain maximumdeflection of the teeth 2367 a, 2367 b, which allows maximum pressurecompensation.

In the form illustrated, the upstream PC portion 2361 a on one side ofteeth 2367 a, 2367 b defines a first volume (e.g., a PC entrance volumeor upstream volume) and the downstream PC portion on the other side ofteeth 2367 a, 2367 b defines a second volume (e.g., the PC exit volumeor downstream volume). In a preferred form, the ratio of the PC entrancevolume to exit volume is within the range of twenty hundredths to fiftyhundredths (0.20 to 0.50), which may also be referred to as the gritresistance ratio. In a preferred form, the ratio of the PC entrancevolume to PC exit volume is between thirty five hundredths andthirty-nine hundredths (0.35 to 0.39). In the form illustrated, theratio between the PC entrance volume to PC exit volume is thirty sevenhundredths plus or minus fifteen thousandths (0.37±0.015). While thesedimensions and ratios have only been discussed with respect to theembodiment of FIGS. 24A-F, it should be understood that they may applyto any of the emitters discussed herein and, without limitation,specifically the emitters of FIGS. 21-24. Furthermore and as withearlier embodiments, it should be understood that the end views of theemitter of FIGS. 24A-F have not been illustrated because these look likethe end views already illustrated in prior embodiments (e.g., FIGS. 10E,11E, etc.).

In the emitter of FIGS. 24A-F, the outlet 2340 includes an alternate setof outlet protrusions 2341 a, 2341 b and 2341 c that are used to preventthe outlet from collapsing completing under increased fluid pressure inthe main tubing or conduit the emitter is mounted to or in. In priorembodiments, these outlet protrusions were either walls extending fromone side wall of the outlet or free standing posts or walls, however, inthe embodiment of FIGS. 24A-F, the outlet protrusions 2341 a, 2341 b and2341 c are walls that extend from a first wall of the outlet 2340 to asecond wall of the outlet 2340 opposite the first wall. By extending oneend of the outlet to the other opposite end of the outlet, theprotrusions 2341 a, 2341 b and 2341 c strengthen the outlet constructionand, thereby, further prevent the outlet 2340 from collapsing under highfluid pressure (which would negatively impact the emitters ability todrip fluid from the outlet as is intended for this structure).

A prior shortcoming noted with outlet protrusions that connect directlyto a side wall of the outlet 2340 is that they can form dead ends orzones that grit or debris collects in, which can ultimately prevent theemitter from operating in a preferred way (e.g., due to clogging,hindering movement, etc.). In the form illustrated in FIGS. 24A-F,however, the emitter 2310 is capable of avoiding such dead endshortcomings by using an outlet wall that is shorter than the height ofthe outlet 2340 and, in a preferred form that has a truncated triangularcross-section (e.g., a triangular shape with the tip or top of thetriangular structure removed). This structure allows the outletprotrusions 2341 a, 2341 b and 2341 c to assist in strengthening thestructural integrity of the outlet bath 2340 and preventing it fromcollapsing fully under increased fluid pressure in the inner lumen ofthe drip line or tubing, while still allowing grit to be flushed throughthe outlet bath 2340 so that the grit is not allowed to collect andinterfere with the operation of the emitter 2310.

In the form illustrated in FIGS. 24A-F, the emitter 2310 is injectionmolded and, thus, has a gate 2341 d where the molten material enters thecavity of the mold. As can be seen in FIGS. 24A, B, D and E, in apreferred form the gate 2341 d is slightly higher than the height of theoutlet protrusions 2341 a, 2341 b and 2341 c, but lower than the heightof the nearby perimeter walls of emitter 2310. In instances where theoutlet floor is movable enough to fully collapse shut against the insidesurface of the tube (or collapse fully under pressure to have the floorcontact the inside surface of the tube at least enough to block theoutlet opening in the tube), having the gate 2341 d be taller than thenearby outlet protrusions 2341 a-c, prevents the outlet floor from beingcapable of such a total collapse so that the emitter continues tooperate as desired. In the form shown, however, the outlet protrusions2341 a-c structurally strengthen the outlet 2340 so that such a totalcollapse of the outlet is not possible.

In addition, by having the gate 2341 d be slightly lower than the nearbyperimeter walls of the outlet 2340, this prevents the gate 2341 d frominterfering with the insertion tooling's ability to form an outlet inthe outer drip line tube aligned with the outlet bath 2340 and/orprevents the gate 2341 d from potentially blocking (partially ortotally) the outlet formed in the outer drip line tubing which wouldprevent the emitter 2310 from operating in the intended way. Forexample, in some forms where the gate 2341 d is generally equal inheight with the height of the nearby perimeter walls and the outletopening in the outer drip line tubing is aligned at least partially withthe gate 2341 d, the gate 2341 d can at least partially obstruct theoutlet opening as the floor of the outlet 2340 moves due to increasedfluid pressure in the inner lumen of the drip line tube. Thisobstruction can be enough to cause the emitter 2310 to interfere withthe normal flow of fluid from the emitter 2310. In some examples, ratherthan having fluid drip from the emitter 2310 and out of the outletformed in the outer drip line tubing as is normally desired, theobstruction caused by the gate 2341 d can cause the fluid to squirt fromthe outlet opening of the outer drip line tube in an undesirablefashion. Although the outer drip line tube is not illustrated in FIGS.24A-F, it is similar to the outer drip line tube illustrated in priorembodiments (e.g., tube 70 in FIG. 1F-H, tube 170 in FIGS. 2E-F, tube270 in FIG. 3A, tube 970 in FIG. 10E, etc.).

While a cross-section of the emitter of FIGS. 24A-F taken along thelongitudinal axis of same has been illustrated in FIG. 24E, it should beunderstood that the cross-sections of the emitters of FIGS. 21A-23Dwould look similar at least with respect to floor thickness, and PR, PCand outlet size. Although the floor of the remainder of the flow passage(e.g., pressure reduction portion) and the outlet illustrated in thatcross-sectional view is illustrated as rather thick, in alternateembodiments moveable floors of different thickness may be used toachieve the amount of floor deformation under pressure that is desiredto compensate for fluid pressure increases in the supply line or mainlumen of the tube. For example, in some forms, a thinner floor may bedesired like that illustrated in FIG. 19B (see floor 1861).

In FIGS. 25A-B and 26, elastomeric emitters like any of those discussedherein are illustrated. In keeping with prior practice, items that aresimilar to those discussed above will use the same latter two-digitreference numeral and including the prefix “24” for the embodiment ofFIGS. 25A-B and “25” for the embodiment of FIG. 26. Thus, the emittersof FIGS. 25A-B and 26 are referred to generally by reference numerals2410 and 2510, respectively, and respectively have bodies 2420, 2520that integrally form inlets 2430, 2530, outlets 2440, 2540, pressurereduction flow passages 2450, 2550 and pressure compensating flowpassages 2460, 2560. Unlike prior embodiments, however, emitters 2410and 2510 further include at least one protrusion extending from anexterior surface of the emitter 2410, 2510 which assists in the removalof the emitter from the injection molding mold and/or the transport ofthe emitter through emitter insertion tooling.

In FIGS. 25A-B, the emitter 2410 includes a plurality of suchprotrusions and the protrusions, are spaced apart from the inlet 2430 ofthe emitter 2410 on the bottom surface of the emitter body 2420 on theemitter body side opposite the side containing the flow passages 2450and 2460 and outlet 2440. In FIGS. 25A-B the plurality of protrusionsare illustrated as convex nubs or round (or rounded) protrusions 2421 a,2421 b, 2421 c, 2421 d, 2421 e, 2421 f, 2421 g and 2421 h. Theprotrusions are aligned with four on one side of the bottom surface ofthe emitter and the other four on the opposite side of the bottomsurface of the emitter such that the protrusion pattern is laid out in asymmetrical orientation. In a preferred form, four protrusions arespaced around the perimeter of each ejector location 2420 c and 2420 dfor the emitter 2410. The ejector locations 2420 c, 2420 d are the areawhere the injection mold tooling will press on to eject the emitter fromthe mold.

In FIG. 26, an alternate protrusion construction is illustrated. Moreparticularly, in this embodiment, a plurality of protrusions is againused, however, in this form, only two protrusions are illustrated andthey are aligned with the ejection areas of the emitter. In this form,the ejector locations are identical to those identified in FIGS. 25A-B(e.g., 2420 c, 2420 d) and the protrusions 2521 a, 2521 b correspond inshape to the ejector locations (meaning the diameters of the protrusions2521 a, 2521 b are the same size as the circles 2420 c, 2420 dillustrated in FIG. 25B). Thus, in this form the protrusions 2521 a,2521 b are round convex (preferably semi-spherical) dimples protrudingfrom the bottom surface of emitter body 2520.

The protrusions 2421 a-h and 2521 a-b may assist in removing the emitterfrom the injection tooling mold, but a primary benefit of theseprotrusions is to help reduce the frictional surface area of the emitter2410, 2510 so that the emitter is easier to transport through theinsertion tooling. For example, such protrusions reduce the frictionalsurface area of the emitter as it is moved from a feeder bowl to aninserter via a conveyor of some form (e.g., conveyor belt, conveyorchain, etc.).

While many of the above-mentioned embodiments illustrate the taperedbaffles of the PC portion extending from separate side walls and angledtoward one another or on a path to intersect one another, it should beunderstood that in alternate embodiments the tapered baffles couldextend from the same side wall of the PC portion and/or could extend outfrom a wall or walls parallel to one another in non-intersecting paths.It should also be understood that one or more features from any one ofthe above mentioned embodiments may be combined with one or morefeatures from any other embodiment to come up with still otherembodiments. For example, a root growth inhibitor, such as a copperplate, and associated retaining structure could be added to any of theemitters of FIGS. 21A-26. Similarly, although specific layouts have beenillustrated, it is to be understood that in further alternateembodiments the layouts may be changed while still following theteachings of the illustrated embodiments to achieve new embodiments(such as to reach a desired flow rate, pressure reduction, pressurecompensation or grit tolerance).

Yet another embodiment in accordance with the invention is illustratedin FIGS. 27A-J and, in keeping with prior numbering practice, isreferred generally by reference numeral 2610. Like prior embodiments,the emitter 2610 is made of an elastomeric body 2620 and integrallydefines an inlet 2630, outlet bath 2640 and a flow channel extendingbetween the inlet 2620 and outlet bath 2640 having a pressure reductionportion 2650 and a pressure compensating portion 2660. In a preferredform, the inlet 2630 includes an inlet protrusion 2632 comprising aperimeter inlet wall that defines an inlet channel terminating at thepressure reduction flow channel 2650, and the outlet bath 2640 includesa plurality of shortened outlet walls 2641 a, 2641 b and 2641 c whichstrengthen the outlet and help flush grit and/or hinder grit buildup asdiscussed in prior embodiments (e.g., FIGS. 24A-F). In the formillustrated, the outlet bath 2640 also includes a reduced height gate2641 d which is lower than the surrounding outlet perimeter walls toprevent the above-mentioned complications when the outlet is formed inthe outer tubing of the assembled drip line and emitter.

Unlike prior embodiments, however, the emitter 2610 includes a pressurereduction passage 2650, pressure compensating passage 2660 and outletbath 2640 that are all at different depths (e.g., have passage floorsurfaces of different depths) or on different planes (e.g., not coplanarwith one another). As best seen in FIGS. 27C and 27E, the pressurereduction passage 2650 has a first depth, the pressure compensatingpassage 2660 has a second depth different than the first depth and theoutlet bath has a third depth different than either the first or seconddepths. In a preferred form, the first depth is smaller than the seconddepth and third depth and the third depth is smaller than the seconddepth. Another way of stating this is that the surface of the pressurereduction passage 2650 floor is in a first plane, the surface of thepressure compensating passage 2660 floor is in a second plane and thesurface of the outlet bath 2640 is in a third plane and none of thefirst, second and third planes are coplanar with one another. Rather,the first plane and third plane are located on one side of the secondplane, but neither the first plane nor the third plane are coplanar withone another.

In the form illustrated in the figures (and as best seen in FIG. 27F),the pressure compensating portion 2660 is capable of having the largestdepth to its floor passage surface because no recess is formed in thebottom of the emitter body 2620 (as has been shown in priorembodiments). Thus, the first side of the emitter body 2620 defines theopen face of the emitter and the side defining at least a portion of theinlet 2630, outlet bath 2640 and flow passage extending therebetween,and the second side of the emitter body 2620 (located opposite the firstside) forms a generally flat opposite side of the emitter body 2620 withthe exception of the perimeter wall of the inlet protrusion 2632extending therefrom (if and when such a structure is present). In apreferred form, the inlet protrusion 2632 is centrally located on adistal end of the emitter body 2620 and formed of a rounded perimeterwall that solely defines the inlet protrusion 2632 of the emitter 2610and no other part of the emitter, however, as has been mentioned above,the protrusion 2632 can be positioned elsewhere on the body 2620 and/ormay not even be included (in which case the entire bottom or second sideof the emitter body will be generally flat and/or coplanar). However, inthe embodiment illustrated in FIG. 27F, the inlet 2630 is located on afirst side of the emitter body 2620 and the outlet bath 2640 is locatedon a second side of the emitter body and the emitter body 2620 furtherdefines an inlet protrusion 2632 extending from the first side of theemitter body 2620 and forming a perimeter wall 2632 about the inlet thatdefines an inlet channel 2631 and the remainder of the first side of theemitter body 2620 is devoid of further protrusions or recesses.

Another difference in emitter 2610 as compared to prior embodiments isthe at least one baffle 2667 positioned on the movable floor 2661 of thepressure compensation portion 2660. The pressure compensating chamber2660 is positioned between the pressure reducing flow channel 2650 andthe outlet bath 2640 to receive fluid from the pressure reducing flowchannel 2650. The chamber 2660 being defined by moveable floor 2661 andat least one tapered baffle 2667 that separates the pressurecompensating chamber into an upstream portion 2660 a and a downstreamportion 2660 b. In the form illustrated, the downstream portion 2660 bis defined by an inner flow passage formed by the at least one taperedbaffle 2667 through which the fluid travels through when transitioningfrom the upstream portion 2660 a to the outlet bath 2640.

Thus, in the form illustrated, the irrigation drip emitter 2610 forms anemitter for attachment to only a portion of an inner circumference of aninner surface of an irrigation drip line tube and includes a discreteelastomeric emitter body 2620 integrally defining: an inlet 2630 forreceiving pressurized fluid from the tube; an outlet bath 2640 fordischarging the fluid from the body 2620; a pressure reducing flowchannel 2650 extending from the inlet 2630 for reducing a pressure andflow of fluid received at the inlet 2630, and a pressure compensatingchamber 2660 positioned between the pressure reducing flow channel 2650and the outlet bath 2640 to receive fluid from the pressure reducingflow channel 2650, the chamber 2660 being defined by a moveable floor2661 and at least one tapered baffle 2667 that separates the pressurecompensating chamber 2660 into an upstream portion 2660 a and adownstream portion 2660 b formed by an inner flow passage defined by theat least one tapered baffle 2667 through which the fluid travels fromthe upstream portion 2660 a to the outlet bath 2640.

In one embodiment, the at least one tapered baffle 2667 has two taperingside portions 2667 a and 2667 b and defines a recess, such as meteringgroove 2667 c, which forms the pinch point 2660 c between the upstreamportion 2660 a and downstream portion 2660 b (as discussed with priorembodiments herein). In a preferred form, the two tapering side portions2667 a, 2667 b are connected to one another at a distal end thereof toform a generally U-shaped or V-shaped structure with a recess 2667 c toallow fluid to flow from the upstream portion 2660 a to the downstreamportion 2660 b formed by the inner flow passage defined by the at leastone tapered baffle 2667. In some forms, the upstream portion 2660 a anddownstream portion 2660 b have respective volumes and the recess 2667 cis generally located in the distal end of the at least one taperedbaffle 2667 and the recess 2667 c defines a recess volume (or pinchpoint volume) that is smaller than both the upstream portion volume andthe downstream portion volume of the pressure compensation chamber 2660.In the embodiment illustrated in FIGS. 27A-J the tapering walls 2667 a,2667 b terminate in the distal end that has a generally circulardiameter of constant height with the exception of the recess 2667 c andinternal flow passage 2660 b. In some forms, the distal end of the twotapering side portions 2667 a, 2667 b comprises an end portion having agenerally circular diameter of constant height with the exception of therecess 2667 c and internal flow passage 2660 b for allowing fluid toflow from the upstream portion 2660 a to the downstream portion 2660 bdefined by the inner flow passage formed by the two tapering sideportions 2667 a, 2667 b.

Another way of stating the above is that the pressure reducing flowchannel 2650 has a first volume and/or cross-sectional area, and thepressure compensating chamber 2660 has a second volume and/orcross-sectional area that is larger than the first volume and/orcross-sectional area of the pressure reducing flow channel 2650.Alternatively, it can be stated with respect to the passage depths asmentioned above. In some forms, the pressure reducing flow channel 2650has first and second side walls connected to one another via a firsttransverse wall (e.g., floor 2650 a) and the pressure compensatingchamber 2660 has side walls or one or more perimeter walls 2660 dconnected via a second transverse wall or floor 2661 and the secondtransverse wall 2661 is positioned at a depth from the top of theemitter 2610 different than the first transverse wall 2650 a so that thesecond volume and/or cross-sectional area of the pressure compensationchamber 2660 is larger than the first volume and/or cross-sectional areaof the pressure reduction passage 2650.

In some embodiments, the first and second perimeter walls are separatedby the egress defined by the pressure compensation chamber 2660 (andspecifically the perimeter wall 2660 d) where fluid flows from thepressure compensation chamber 2660 to the outlet bath 2640. Thus, thepressure reducing flow channel 2650 has a pressure reducing flow channelfloor 2650 a of a first depth and the pressure compensation chamber 2660has a moveable floor 2661 of a second depth that is deeper than thefirst depth. In a preferred form, the emitter body 2620 has an emitterbody height and the first depth associated with the pressure reducingflow channel 2650 is less than fifty percent the emitter body height atthe pressure reducing flow channel 2650 and the second depth of thepressure compensation chamber 2660 is greater than fifty percent theemitter body height at the pressure compensation chamber 2660. Forexample, in one form, the first depth of the pressure reduction portion2650 is less than twenty-five percent the emitter body height at thepressure reducing flow channel 2650 and the second depth of the pressurecompensating chamber 2660 is greater than seventy-five percent theemitter body height at the pressure compensation chamber 2660.

In the form shown in FIGS. 26A-J, the tapered walls 2667 a, 2667 bextend from separate or different side walls defining chamber 2660. Moreparticularly, in the form illustrated, the perimeter wall 2660 d definesa generally rectangular side wall with interruptions at the ingress 2660e and egress 2660 f (e.g., ingress and egress passages) of the pressurecompensation chamber 2660. In a preferred form, the perimeter or sidewalls 2660 d of the pressure compensation chamber 2660 are defined bythe emitter body 2620 and include first, second, third and fourth sidewalls positioned in a generally rectangular orientation, with the firstand second side walls positioned parallel to one another (preferably onsides of the emitter body 2620) and having a generally flat uppersurface, and the third and fourth side walls positioned parallel to oneanother and generally transverse the first and second side walls, withthe third and fourth side walls having a curved upper surface with afirst radius of curvature that corresponds to an interior surface of anirrigation drip tube like the perimeter walls located at the ends of theemitter body (as opposed to the walls on the sides of the emitter body).

In FIGS. 26A-J, the first tapered wall 2667 a extends from a firstperimeter wall and the second tapered wall 2667 b extends from a secondperimeter wall neighboring and generally transverse the first perimeterwall. In other forms, the pressure compensating chamber 2660 may bedefined by at least two sidewalls bordering the moveable floor 2661 andthe at least one tapered baffle 2667 may comprise a first tapering wall2667 a and a second tapering wall 2667 b with the first and secondtapering walls 2667 a, 2667 b extending from different chamber sidewallstoward a center region of the pressure compensating chamber 2660 andtoward one another. In some forms like those discussed above (FIGS.22A-E, 23A-E, 24A-F, etc.) the tapering walls 2667 a, 2667 b may notmeet, and in some cases they may overlap or come close to overlapping toform a pinch point 2060 c between the upstream portion 2060 a and thedownstream portion 2060 b. In the form illustrated in FIGS. 27A-J, thetapering walls 2667 a, 2667 b extend toward one another and the centerof the pressure compensating chamber 2660 until contact is madetherebetween (or between the distal ends of tapering walls 2667 a, 2667b), a recess 2667 c being formed proximate the distal ends of the firstand second tapering walls 2667 a, 2667 b to provide a passage 2660 cfrom the upstream portion 2660 a of the pressure compensating chamber2660 to the downstream portion 2660 b of the pressure compensatingchamber 2660 formed between the first and second tapering walls 2667 a,2667 b.

As with prior embodiments discussed above, the emitter of FIGS. 27A-J isintended to be mounted inside of a drip line tube at regular intervalstherein in order to form irrigation drip line or drip line tubing. Thus,in addition to emitter 2610, there is contemplated herein an irrigationdrip line tube including a tube having an inner surface and an outersurface with the inner surface defining an inner circumference of thetube, and a plurality of discrete elastomeric emitters 2610 connected toonly a portion of the inner circumference of the inner surface of thetube and at regular intervals therein. In a preferred form, eachelastomeric emitter body 2620 integrally defining: an inlet 2630 forreceiving pressurized fluid from the tube; an outlet bath 2640 fordischarging the fluid from the body 2620; a pressure reducing flowchannel 2650 extending from the inlet 2630 for reducing a pressure andflow of fluid received at the inlet, and a pressure compensating chamber2660 positioned between the pressure reducing flow channel 2650 and theoutlet bath 2640 to receive fluid from the pressure reducing flowchannel 2650, the chamber 2660 being defined by a moveable floor 2661and at least one tapered baffle 2667 that separates the pressurecompensating chamber 2660 into an upstream portion 2660 a and adownstream portion 2660 b formed by an inner flow passage defined by theat least one tapered baffle 2667 through which the fluid travels fromthe upstream portion to the outlet bath 2640.

In yet other embodiments of the invention and as has been discussedherein with respect to FIGS. 16A-B and 17A-B, it may be desirable toform an emitter out of two different materials to assist withtransporting the emitter during the drip line manufacturing processand/or the bonding of the emitter to the extruded tubing to form thedesired irrigation drip line. For example, another embodiment of theinvention is the poly-material emitter illustrated in FIGS. 28A-J. Inkeeping with prior practice, similar latter two digit reference numeralswill be used for items that are similar to those discussed in priorembodiments, but adding a prefix of “27” to the two-digit referencenumeral to distinguish one embodiment from others. Thus, in FIGS. 28A-J,the emitter is referred to generally as emitter 2710 and includes a body2720 defining an inlet 2730, outlet bath 2740 and flow path extendingtherebetween. However, unlike prior embodiments, in the formillustrated, the body only defines the pressure reduction portion 2750of the flow passage and is made of a polyethylene instead of athermoplastic elastomeric component (e.g., TPO). In this embodiment,only the pressure compensating chamber 2760 is made of a thermoplasticelastomeric component (e.g., TPO). In this way, the majority of theemitter 2710 is made of a more rigid and easily transportable andbondable polyethylene material and only a small portion is made of anelastomeric material (which tends to be harder to transport throughoutinsertion tooling or machinery and which tends to be harder to bondrepeatably to extruded tubing.

In a preferred form the polyethylene body 2720 and thermoplasticelastomeric chamber 2760 are formed in a two-shot molding process and ina way that the thermoplastic elastomeric chamber 2760 chemically bondsto the rigid polyethylene material without the need for interlockingfeatures or cross-linking between the two distinct materials. In otherforms, the emitter 2710 may be formed in separate steps, such as byhaving the elastomeric pressure compensating portion or chamber 2760formed separately and inserted or disposed into a socket or seat 2720 cdefined by the rigid polyethylene body 2720. In some forms, the rigidbody 2720 may further be formed with an inlet protrusion 2732 similar tothose discussed in prior embodiments that defines an inlet channel 2731terminating in and in fluid communication with the pressure reductionportion 2750 of emitter 2710.

Regardless of the manufacturing process used, the body 2720 willpreferably define a seat 2720 c having at least one supporting surfaceupon which the pressure compensating portion 2760 will be nested orsupported. In the form illustrated, the seat 2720 c is formed from wallsextending out transversely from the boundary or perimeter walls 2720 dthat define the socket within which the pressure compensating member2760 is disposed. The seat 2720 c will further define an inner openingthat allows at least a portion of the bottom surface of the movablefloor 2761 of the pressure compensation member 2760 to be exposed tofluid traveling through the drip line so that the fluid traveling in thedrip line can move the movable floor 2761 and cause the pressurecompensating member 2760 to compensate for increases or decreased in thefluid supply line pressure. In the form illustrated, the seat 2720 c isformed such that it only overlaps with a minimal portion of the pressurecompensating member 2760 and the opening defined by the seat 2720 c iscentrally located within the body 2720 and leaves exposed a majority ofthe bottom surface of the pressure compensating member 2760 (e.g.,greater than 90% of the bottom surface of the pressure compensatingmember 2760 remains exposed).

Turning now more particularly to the to the pressure compensating member2760 (and as best illustrated in FIGS. 28B, E and H), it should beunderstood that in a preferred form, a pressure compensating member 2760for a poly-material emitter 2710 is disclosed herein integrallydefining: a flexible floor 2761; side walls 2760 d extendingsubstantially about a perimeter of the flexible floor 2761 and includingan ingress opening 2760 e and an egress opening 2760 f; and at least onetapering baffle (e.g., 2767 a, 2767 b) that separates the flexible floor2761 and pressure compensating member 2760 into an upstream portion 2760a and a downstream portion 2760 b with both the upstream portion 2760 aand downstream portion 2760 b having respective volumes orcross-sectional areas and the volume or cross-sectional area of theupstream portion 2760 a being larger than the volume or cross-sectionalarea of the downstream portion 2760 b to assist the pressurecompensating member in flushing grit therethrough in a manner similar tothat discussed above with respect to FIGS. 22A-E, 23A-E, 24A-F, etc.).

In a preferred form, the perimeter or side walls 2760 d of the pressurecompensation chamber 2760 include first, second, third and fourth sidewalls positioned in a generally rectangular orientation, with the firstand second side walls positioned parallel to one another and having agenerally flat upper surface (preferably configured to be positionedalong sides of the emitter body 2720), and the third and fourth sidewalls positioned parallel to one another and generally transverse thefirst and second side walls (e.g., transverse to the longitudinal axisof the emitter body 2720), with the third and fourth side walls having acurved upper surface with a first radius of curvature that correspondsto an interior surface of an irrigation drip tube (e.g., like the wallsat the distal ends of the emitter body 2720). In a preferred form and asbest illustrated in FIG. 28E, the flexible floor 2761 has a first sideupon which the at least one tapering baffle (e.g., baffles 2767 a, 2767b) is connected, and a second side located opposite the first side, andwherein the flexible floor is shaped so as to be concave on the secondside and convex on the first side. The flexible floor 2761 has a secondradius of curvature that corresponds in shape to the first radius ofcurvature of the upper surfaces of the third and fourth side walls 2760d. In the form shown, the first, second, third and fourth side walls2760 d extend above the first side of the flexible floor 2761 andterminate in the generally flat upper surfaces of the first and secondside walls and the curved upper surfaces of the third and fourth sidewalls, respectively, and the first, second, third and fourth side walls2760 d further extend below the second side of the flexible floor andterminate in generally flat and coplanar bottom surfaces. Due to thecurve of the upper surfaces of the third and fourth wall and thegenerally flat upper surfaces of the first and second wall, the uppersurfaces of walls 2760 d are not coplanar.

In a preferred form, the elastomeric body of the pressure compensatingmember 2760 will further define a protruding portion proximate at leastone of the ingress opening and/or the egress opening, or both to ensurea smooth transition from pressure reduction portion 2750 and to outletbath 2740, respectively. In the form illustrated in FIGS. 28A-J, theelastomeric body of the pressure compensating member 2760 includes afirst protruding portion aligned with the ingress 2760 e and a secondprotruding portion aligned with the egress 2760 f and the first andsecond protruding portions extend out beyond a boundary defined by theside walls 2760 d. In the form illustrated, the second protrudingportion at egress 2760 f extends out further from the boundary definedby the adjacent upstanding side wall 2760 d farther than the firstprotruding portion aligned with the ingress 2760 e does from itsadjacent upstanding side wall 2760 d. In view of this configuration, itshould be understood that the emitter body 2720.

In the form shown in FIGS. 28A-J, the pressure compensating member 2760includes at least a first side wall and a second side wall (e.g., anyone of the perimeter walls 2760 d) and the at least one tapering bafflecomprises a first tapering baffle 2767 a extending from a first sidewall and a second tapering baffle 2767 b extending from a second sidewall, with the first and second tapering baffles 2767 a, 2767 bextending toward a center of the flexible floor 2761 and toward oneanother to define the upstream portion 2760 a and downstream portion2760 b of the pressure compensating member 2760. Note, the first andsecond side walls referenced here could be any of the first, second,third and fourth side walls 2760 d mentioned above or could be alternateconfigurations (e.g., such as an ellipse shaped structure with twocurved perimeter walls that connect to one another to form the ellipse,etc.). In the form shown, one of the first and second tapering baffles2767 a, 2767 b extends further toward the center of the flexible floor2761 than the other tapering baffle 2767 b, 2767 a (e.g., in FIGS.28A-J, tapering baffle wall 2767 a extends further toward the center offloor 2761 than tapering baffle wall 2767 b).

It should be understood, that disclosed herein are various embodimentsof emitters including some that are integral elastomeric emitters madeentirely of one material, others are poly-material emitters and stillothers are simply components for use with emitters such as theelastomeric pressure compensation member 2760 illustrated in FIGS.28A-J. In some forms, just the pressure compensating member 2760 may beprovide for use with other emitter bodies (e.g., off the shelf emitterbodies, etc.). In other forms, however, the elastomeric pressurecompensating member 2760 may be provided along with a rigid emitter body2720 and, preferably having the pressure compensating member 2760disposed within an opening formed by the rigid emitter body 2720. Asmentioned above, in some forms the emitter body 2720 defines a seat 2720c within which the pressure compensating member 2760 is disposed.

Another exemplary emitter in accordance with such disclosure is shown inFIGS. 29A-H. In this form a pressure compensating member very similar topressure compensating member 2760 is illustrated connected to anotherrigid emitter similar to existing conventional emitters. Unlike suchconventional emitters, however, the emitter body has been altered toaccommodate a pressure compensating member in accordance with thedisclosure herein. In keeping with prior practice, the emitter of FIGS.29A-H will use similar latter two-digit reference numerals but with theprefix 28 in order to identify similar items and distinguish oneembodiment from another. Thus, in the form illustrated, the emitter isreferred to generally by reference numeral 2810 and includes an emitterbody 2820 defining an inlet 2830, and outlet 2840 and a flow passageextending therebetween partly made up by a pressure reduction portion2850 and a pressure compensating member 2860 similar to the pressurecompensating member 2760 discussed above with respect to FIGS. 28A-J.More particularly, a poly-material emitter 2810 is illustrated in FIGS.29A-H having a rigid emitter body 2820 integrally defining an inlet2830, an outlet 2840 and a pressure reducing flow passage 2850 extendingfrom the inlet. The rigid emitter body 2820 further defining an openingfor receiving pressure compensating member 2860. As best illustrated inFIGS. 29B and 29H, in a preferred form, the rigid body 2820 defines aseat 2820 c for supporting at least a portion of the pressurecompensating member 2860. The elastomeric pressure compensating member2860 integrally defines a flexible floor 2861 and side walls 2860 dextending substantially about a perimeter of the flexible floor 2861 andincluding an ingress opening or portion 2860 e and an egress opening orportion 2860 f, and at least one tapering baffle that separates theflexible floor 2861 and pressure compensating member 2860 into anupstream portion 2860 a and a downstream portion 2860 b. In thepreferred form illustrated, the at least one tapering baffle includesfirst tapering baffle 2867 a and second tapering baffle 2867 b, with thefirst tapering baffle 2867 a extending further toward the center of themovable floor 2861 than the second tapering baffle 2867 b (e.g., thefirst tapering baffle 2867 a extending further upstream than the secondtapering baffle 2867 b). Both the upstream portion 2860 a and downstreamportion 2860 b have respective volumes or cross-sectional areas and thevolume or cross-sectional area of the upstream portion is preferablymade larger than the volume or cross-sectional area of the downstreamportion to assist the pressure compensating member 2860 in flushing gritthrough the emitter 2810.

In the form illustrated in FIGS. 29A-H, the seat 2820 c of the rigidemitter body 2820 is defined by a step or shelf formed in the rigidemitter body and at least a portion of the pressure compensating memberis rested on the step or shelf 2820. As with at least one priorembodiment the side walls of the pressure compensating member 2860 willrest above the seat 2820 c and include first, second, third and fourthside walls positioned in a generally rectangular orientation, with thefirst and second side walls positioned parallel to one another andhaving a generally flat upper surface, and the third and fourth sidewalls positioned parallel to one another and being generally transverseto the first and second side walls, with the third and fourth side wallshaving a curved upper surface with a first radius of curvature thatcorresponds to an interior surface of an irrigation drip tube. Theflexible floor 2861 has a first side upon which the at least onetapering baffle is connected (e.g., first baffle 2867 a and secondbaffle 2867 b), and a second side located opposite the first side, andwherein the flexible floor 2861 is shaped so as to be concave on thesecond side and convex on the first side. The first side of flexiblefloor 2861 having a second radius of curvature that corresponds in shapeto the first radius of curvature of the upper surfaces of the third andfourth side walls so as to give the flow passages of the emitter agenerally uniform cross-section despite the curvature of the inner tubesurface to which the emitter 2810 is connected.

Again, as best illustrated in FIGS. 29B and 29H, the first, second,third and fourth side walls of pressure compensating member 2860 extendabove the first side of the flexible floor 2861 and terminate in thegenerally flat upper surfaces of the first and second side walls and thegenerally curved upper surfaces of the third and fourth side walls. Inaddition, the first, second, third and fourth side walls of pressurecompensating member 2860 further extend below the second side of theflexible floor 2861 and terminate in generally flat and coplanar bottomsurfaces designed to rest at least partially on seat 2820 c of rigidemitter body 2820.

The pressure compensating member 2860 further defines a protrudingportion proximate at least one of the ingress opening and/or the egressopening. In the form illustrated, the pressure compensating member 2860has a first ingress protruding portion 2860 e proximate the ingressopening of the pressure compensating member 2860 and a second egressprotruding portion 2860 f proximate the egress opening of the pressurecompensating member 2860. In the illustrated form, the ingress andegress protrusions 2860 e, 2860 f protrude or extend out beyond aboundary defined by the perimeter or side walls 2860 d of pressurecompensating member 2860.

As with the prior embodiment of FIGS. 28A-J, pressure compensationmember 2860 includes side walls 2860 d having at least a first side walland a second side wall and the at least one tapering baffle comprises afirst tapering baffle 2867 a extending from the first side wall and asecond tapering baffle 2867 b extending from the second side wall, withthe first and second tapering baffles 2867 a, 2867 b extending toward acenter of the flexible floor and toward one another to define theupstream portion 2860 a and downstream portion 2860 b of the pressurecompensating member. As mentioned, the first tapering baffle 2867 aextends further toward the center of the flexible floor 2861 than thesecond tapering baffle 2867 b. The first tapering baffle 2867 a extendsupstream than the second tapering baffle 2867 b. In this form, thebaffles 2867 a, 2867 b extend generally from corner regions of thepressure compensation member 2860 and on opposite sides of the pressurecompensation member, however, it should be understood that in alternateembodiments the baffles could extend from a common wall or from cornersthat are not only on opposite sides of the pressure compensation member2860, but also that are kitty or catty corner to one another (e.g.,diagonal from one another).

In addition to disclosing herein pressure compensating members andemitters, it should also be understood that various forms of drip lineare also disclosed herein using any of the above mentioned pressurecompensating members or emitters. In addition, it is contemplated thatcomponents or features of one embodiment can be combined with one ormore embodiments to come up with entire new embodiments in accordancewith this disclosure. For example, an irrigation drip line iscontemplated herein having a tube having an inner surface and an outersurface with the inner surface defining an inner circumference of thetube, and a plurality of discrete emitters (any disclosed herein)connected to only a portion of the inner circumference of the innersurface of the tube and at regular intervals therein. For example, insome forms, the discrete emitters may take the shape of the emittersdepicted in FIGS. 21A-28H. In other forms, the emitters may use featuresfrom any of the above emitters to form new emitters placed at regularintervals within the drip line tube. In some instances, this will meanemitters with uniform elastomeric emitter bodies will be used in thedripline, while in other instances poly-material emitters may be used inthe dripline.

In addition to the above-mentioned emitter embodiments, there has beendisclosed herein numerous different methods. For example, methods ofmaking grit tolerant emitters are disclosed herein. In some forms, suchmethods include providing an emitter having an inlet, an outlet and aflow passage extending between the inlet and outlet and in fluidcommunication with same, the flow passage having a pressure compensatingportion with tapered baffles capable of moving between a first positionhaving a flow passage opening of a first cross-section and a secondposition having a flow passage opening of a second cross-section smallerthan the first cross-section to compensate for increases in fluidpressure traveling within a fluid line that the emitter is connected to,the tapering baffles separating the pressure compensating portion of theemitter into an upstream portion and a downstream portion; andconfiguring the tapering baffles such that the upstream portion of thecompensating portion is larger in area and volume than the downstreamportion in order to ensure greater pressure will be applied to theupstream portion of the pressure compensating portion to assist influshing grit from the pressure compensating portion of the emitter.That is, as grit blockage reaches a point where the desired flow rate isnot being provided, pressure will build-up on the upstream side of theteeth in the PC chamber. This will cause the floor to move away from theinner surface of the tube, thereby opening up the span between the teethand the inner surface of the tube to allow the grit to pass over anddownstream of the teeth. The size of the upstream floor and volume ofthe upstream portion is determined based on being able to provide theappropriate amount of flushing pressure. Thus, this are and volume canbe changed to accommodate design parameters where larger or smallerpressure thresholds are desired. Further, a step is preferably formed ineach tooth in order to ensure that the teeth cannot stop all fluid flowso that fluid flow continues downstream and can further assist with theflushing of grit out of the emitter. The step in the teeth also helpsthe desired movement to occur in the PC portion of the emitter on a moreconsistent and repeatable basis from emitter to emitter. Other methodsinclude methods of reducing pressure of fluid flowing through anemitter, methods of compensating for fluid line pressure fluctuationsand methods for preventing grit buildup.

Again, the different emitter designs or layouts may be formed by asingle, one-piece emitter, however, in other forms, they may be formedby interchanging various emitter portions to obtain the emitterproperties desired for a particular application. In addition to havingthese interchangeable portions or in lieu of having theseinterchangeable portions, it should be understood that the mold forproducing the emitter could be configured with different inserts toproduce emitters of different types (e.g., emitters of different flowrates, emitters of different pressure compensation characteristics (ifany pressure compensating), emitters with different flow channel shapesor sizes, etc.).

Thus, disclosed herein is also an open-face non-cylindrical irrigationdrip emitter for attachment to only a circumferential portion of aninner surface of an irrigation drip line tube carrying pressurized fluidcomprising an emitter body having an inlet portion, flow passage portionand outlet portion, wherein at least one of the inlet portion, flowpassage portion or outlet portion is formed from a first insert disposedin the emitter body that can be interchanged with a second insert inorder to provide an emitter with a different performance characteristic.In one form, the flow passage portion of the open-face non-cylindricalirrigation drip emitter includes both a pressure reduction portion and apressure compensation portion and at least one of the inlet portion,pressure reduction portion, pressure compensation portion and outletportion is formed by the first insert disposed in the emitter body thatcan be interchanged with the second insert in order to provide anemitter with a different performance characteristic. an emitter bodyhaving an inlet portion, flow passage portion and outlet portion,wherein at least one of the inlet portion, flow passage portion oroutlet portion is formed as an interchangeable or swappable insert thatcan be changed or replaced with a second emitter insert portion in orderto provide an emitter with a different design or performancecharacteristic. Thus, the first insert disposed in the emitter bodycomprises an interchangeable or swappable insert that can beinterchanged or swapped with a second insert having a different designor performance characteristic to alter how the emitter performs. Thisconfiguration provides yet another way in which emitters with differentperformance characteristics may be made or formed (e.g., emitters withdifferent flow rates, reaction rates to changes in fluid line pressure,etc.).

In addition to the above embodiments, it should be understood thatvarious methods of manufacturing or assembling irrigation drip lines,methods of compensating for pressure in a supply line (e.g., increasesor decreases in supply line fluid pressure), methods of manufacturing anemitter and methods of reducing fluid flow pressure are also disclosedherein. For example, a method of assembling an irrigation drip line isdisclosed which comprises providing a drip emitter according to any ofthe above mentioned embodiments where at least one of the inner andouter baffle walls include a tapered baffle wall section, extruding adrip line tube and inserting the provided drip emitter into the dripline tube as it is extruded such that upper surfaces of the emitterother than the tapered baffle wall section are bonded with an innersurface of the extruded drip line tube to form a sealed engagement sothat a pressure reduction flow channel is formed between the inlet andoutlet area of the emitter. In a preferred form, the upper surfaces ofthe non-tapered baffle walls are bonded to the inner surface of theextruded drip line tube to form this sealed engagement so that anelongated tortuous passage is formed between the inlet and outlet of theemitter.

In addition to this method, there are disclosed several methods ofcompensating for pressure in irrigation drip emitters. For example, amethod of compensating for pressure in an irrigation drip emitter isdisclosed comprising providing a drip emitter according to any of theabove-mentioned embodiments wherein the baffle walls have upper surfaceswith a first radius of curvature and the inner baffle wall has a firstportion of constant height and a second portion of tapering height thatis variably moveable between a first low pressure position wherein theupper surface of the second portion is not generally level with theupper surface of the first portion and fluid can flow over the uppersurface of the second portion at low fluid pressures and a second highpressure position wherein the upper surface of the second portion islevel with the upper surface of the first portion such that fluid isprevented from flowing over the upper surface of the second portion andthe cross-section of the flow channel is reduced and the extent of theflow channel is effectively lengthened, and moving the second portion ofthe inner baffle wall between the first low pressure position whereinthe upper surface of the second portion is not level with the uppersurface of the first portion and fluid can flow over the upper surfaceof the second portion at low fluid pressures and the second highpressure position wherein the upper surface of the second portion movestoward a position that is level with the upper surface of the firstportion so that fluid is prevented or at least hindered from flowingover the upper surface of the second portion to reduce the cross-sectionof the flow channel and effectively lengthen the extent of the flowchannel the fluid has to pass through at high fluid pressure in order tocompensate for an increase in fluid supply pressure, and moving variablythe second portion of the inner baffle wall toward and/or to the secondhigh pressure position to compensate for an increase in fluid pressureand toward and/or to the first low pressure position to compensate for adecrease in fluid supply pressure.

Alternatively, a method of compensating for pressure in an irrigationdrip emitter is disclosed which comprises providing a drip emitteraccording to any of the above-mentioned embodiments wherein the bafflewalls have upper surfaces with a first radius of curvature and the innerbaffle wall terminates in a first structure and the outer baffle wallincludes a second structure that generally corresponds in shape and/ormeshes with the first structure and is positioned proximate the firststructure, with the first and second structures tapering in heighttoward one another and being variably moveable between a first lowpressure position wherein the upper surfaces of the tapered structuresare not level with the upper surfaces of the baffle walls and fluid canflow over the tapered structures at low fluid pressure and a second highpressure position wherein the upper surfaces of the tapered structuresare level with the upper surfaces of the baffle walls and fluid isprevented from flowing over the tapered structures to reduce thecross-section of the flow channel proximate the first and secondstructures and effectively lengthen the extent or amount of the flowchannel the fluid has to pass through at high fluid pressure, and movingvariably the first and second structures toward and/or to the secondhigh pressure position to compensate for an increase in fluid supplypressure and toward and/or to the first low pressure position tocompensate for a decrease in fluid supply pressure.

Alternatively, another method of compensating for pressure in anirrigation drip emitter is disclosed comprising providing an irrigationdrip emitter according to any of the embodiments disclosed herein,wherein the baffle walls have upper surfaces with a first radius ofcurvature and the inlet includes a plurality of inlet openings orpassages extending from a surface of the body exposed to the pressurizedsupply fluid to the pressure reducing flow channel, each inlet passageextending through a boss with a terminal end extending progressivelyfurther into the pressure reducing flow channel, each of the terminalends moveable variably between an open position wherein the uppersurface of the terminal end of the boss is not at the same general levelas the baffle walls (or with the upper surfaces of the terminal end andbaffle walls not being at a common radius of curvature) so that fluidcan continue to flow through the boss and into the flow channel and aclosed position wherein the terminal end of the boss is generally levelwith the upper surfaces of the baffle walls and has a generally commonradius of curvature as the first radius of curvature of the baffle wallsso that fluid is prevented from flowing through the boss or inlet sleeveand into the flow channel, and moving variably the inlet openings orterminal ends of the bosses toward and/or to the second high pressureclosed positions to compensate for an increase in fluid supply pressureand toward and/or to the first low pressure open positions to compensatefor a decrease in fluid supply pressure.

In the above examples, it should be clear that movement of the moveablewalls or structures to compensate for fluid pressure increases anddecreases can either be complete movements from a first limit of travelto a second limit of travel (i.e., from a furthest most open position toa furthest most closed position and vice versa), or alternatively, maysimply be movements toward one or more of those limits of travel withoutthose limits actually having been reached (i.e., movement toward afurthest most open position to a furthest most closed position and viceversa). In addition, the material chosen for the emitter body (e.g., 20,120, 220 above), may be selected such that such movement happens at adesired pace. For example, if a quick opening and closing is desired, amaterial that is more flexible or has a lower Durometer value may beselected. Whereas, if a slower or more gradual opening and closing (ortransitioning from one or the other) is desired, a material that is lessflexible or that has a higher Durometer value may be selected.

There also are disclosed herein various methods for processing gritthrough an emitter or clearing emitters and/or drip lines ofobstructions. For example, one method for processing grit comprisesproviding an emitter of the type discussed above, adjusting the fluidpressure that the emitter is subjected to in a supply line to alter thesize or shape of the flow channel to expel any obstructions clogging theemitter (e.g., obstructions clogging an inlet, flow channel, outlet,etc.). In one form, this is done by decreasing the fluid pressure tomaximize the cross-sectional area of the flow channel and/or create acentral flow channel through which any obstructions such as grit orother particulates may be flushed. In another form, this is done byincreasing the fluid pressure to cause the baffle walls of the flowchannel to deflect, bend or tip so that obstructions can pass throughthe flow channel or be carried out of the emitter via the high pressurefluid passing therethrough.

Other methods disclosed herein include methods for manufacturing anemitter comprising providing an emitter body made-up of a singlematerial or unitary body construction defining an emitter inlet, atleast part of the tortuous flow passage and an outlet bath and insertinga root inhibiting member in or proximate to the outlet bath of theemitter to inhibit roots from obstructing the emitter or operationthereof once the unitary body member is connected to tubing to form thefinished emitter. In another form, a method of manufacturing an emittercomprises providing an emitter body made-up of a single material orunitary body construction defining the emitter inlet, at least part ofthe tortuous flow passage and an outlet bath and elongating the inletopening to draw fluid from closer to the center of the inner lumen ofthe tube in an effort to draw fluid with less grit to inhibit grit fromobstructing the emitter or operation thereof once the unitary bodymember is connected to tubing to form the finished emitter product.Another method disclosed relates to the manufacturing of an emittercomprising providing an unitary emitter body defining an emitter inlet,at least a portion of the tortuous flow passage and an outlet bath andboth inserting a root inhibiting member in or proximate to the outletbath and elongating the inlet opening to draw fluid from closer to themiddle or center region of the inner lumen. Yet another method disclosedrelates to a method of controlling a pressure compensation portion of anemitter by defining a trampoline area that allows the pressurecompensation portion to move as desired. For example, such a method mayinclude increasing the size of the trampoline area of the pressurecompensation member on one side of the emitter to an area larger thanthe overall size of the pressure compensation member area located on theopposite side of the emitter (e.g., the area containing the moveableteeth or flippers) to make the emitter more responsive to fluid pressureincreases and decreases. Conversely, the size of the trampoline area maybe reduced in order to make the emitter less responsive to fluidpressure increases and decreases.

Another method comprises a method of manufacturing and/or inserting anemitter into tubing which includes providing an emitter body having aninlet, outlet and tortuous flow passage connecting the inlet and outletin fluid communication with one another, providing a carrier in whichthe emitter body is disposed or to which the emitter body is connected,and connecting the emitter body to the carrier so that the emitter bodycan more easily be transported through an insertion tool and into driptubing. In a preferred form, the connection between emitter body andcarrier is permanent such that the carrier remains with the emitter bodyafter the emitter is installed into tubing. However, in alternate forms,the method may further include separating the carrier from the emitterbody once the emitter body is installed into the tubing.

In addition, a method for reducing problems associated withcross-linking and bonding between an emitter and tubing have also beendisclosed herein. For example, such a method may include providing anemitter body having an inlet, outlet and fluid passage connected betweenthe inlet and outlet, and connecting a bracket to the emitter body madeof a material that easily bonds with tubing as the tubing is beingextruded to ensure a good connection between the emitter body and tubingthat is free of cross-linking or bonding defects.

It should also be understood that methods of improving and/orcontrolling emitter pressure compensation are also disclosed herein. Forexample, methods of improving and/or controlling emitter pressurecompensation by forming a step in at least one moveable baffle tooth orflipper of the pressure compensator of the emitter have been disclosed(or forming a step in one or more baffle teeth/flippers for thispurpose). Similar such methods have been disclosed that include forminga plurality of steps in a plurality of moveable baffles to help improveand/or control emitter pressure compensation. Methods of securing a rootgrowth inhibitor to an emitter and methods for preventing and/orhindering grit build-up in an emitter and, specifically, an emitteroutlet also have been disclosed.

In view of the above, it should be appreciated that a method ofmanufacturing an open face flat in-line emitter has been disclosedherein including one or more of the following additional features: aroot growth inhibitor member, an inlet projection and/or a carrier forassisting with installation of the emitter into tubing and/or bonding ofthe emitter to tubing. In addition, methods of manufacturing orassembling non-pressure compensating components are disclosed as aremethods of manufacturing or assembling pressure compensating and/ornon-pressure compensating emitters with interchangeable parts.Similarly, methods of manufacturing or assembling customizable emittersand methods of customizing or configuring emitters are also disclosedherein. In addition to providing methods of customizing or configuringemitters with interchangeable inserts, there are also methods ofcustomizing or configuring emitters using a mold. The different emitterdesigns or layouts may be formed by interchanging various emitterportions to obtain the emitter properties desired for a particularapplication. In addition to having these interchangeable portions, itshould be understood that the mold for manufacturing or producing theemitter could alternatively be configured with different inserts toproduce emitters of different types (e.g., emitters with differentdesigns or layouts, emitters with different flow rates, emitters withdifferent pressure compensation characteristics (if any pressurecompensating), emitters with different flow channel shapes or sizes,etc.).

In some exemplary forms, the method for manufacturing an open-facenon-cylindrical irrigation drip emitter for attachment to only acircumferential portion of an inner surface of an irrigation drip linetube carrying pressurized fluid comprises providing an emitter bodyhaving an inlet portion, flow passage portion and outlet portion,wherein at least one of the inlet portion, flow passage portion oroutlet portion is formed as an interchangeable or swappable insert, andinterchanging or swapping the interchangeable or swappable insert with asecond emitter insert in order to alter the design or performance of theemitter. In other exemplary forms, the method of manufacturing anopen-face non-cylindrical irrigation drip emitter for attachment to onlya circumferential portion of an inner surface of an irrigation drip linetube carrying pressurized fluid comprises providing a mold for formingan emitter body having an inlet portion, flow passage portion and outletportion, wherein the mold includes at least one interchangeable orswappable insert for forming at least one of the inlet portion, flowpassage portion and outlet portion, and interchanging or swapping theinterchangeable or swappable insert with a second emitter insert inorder to alter the design or performance characteristic of the emittermanufactured by the mold. In still other exemplary forms, the method forimproving the pressure compensating performance of a non-cylindricalirrigation drip emitter for attachment to only a circumferential portionof an inner surface of an irrigation drip line tube carrying pressurizedfluid comprises providing an emitter body defining an inlet area, outletarea and a flow channel therebetween connecting the inlet and outletareas, the flow channel defining a pressure reduction portion and apressure compensating portion having a first volume at lower fluidpressure and a second volume smaller than the first volume at higherfluid pressure to restrict flow through the channel, wherein thepressure compensating portion includes at least one baffle tooth havinga base, a tip and an upper surface extending between the base and tip,and forming at least one step in the base of the at least one baffletooth so the base of the tooth is positioned at a height different froma proximate upper bonding surface of the emitter in order to improvepressure compensating performance of the emitter.

Another method disclosed herein is a method of manufacturing anirrigation drip emitter for attachment to only a portion of an innercircumference of an inner surface of an irrigation drip line tube likethat depicted in FIGS. 27A-J. For example, a method of manufacturing anemitter comprising providing an elastomeric material, and molding theelastomeric material into a discrete elastomeric emitter body integrallydefining: an inlet for receiving pressurized fluid from the tube; anoutlet bath for discharging the fluid from the body; a pressure reducingflow channel extending from the inlet for reducing a pressure and flowof fluid received at the inlet, and a pressure compensating chamberpositioned between the pressure reducing flow channel and the outletbath to receive fluid from the pressure reducing flow channel, thechamber being defined by a moveable floor and at least one taperedbaffle that separates the pressure compensating chamber into an upstreamportion and a downstream portion formed by an inner flow passage definedby the at least one tapered baffle through which the fluid travels fromthe upstream portion. Similarly, a method of manufacturing a drip linehaving emitters similar to those illustrated in FIGS. 27A-J is alsocontemplated. More particularly, a method of manufacturing an irrigationdrip line tube including: providing an elastomeric material; molding theelastomeric material into a plurality of discrete elastomeric emitterbodies, each emitter body integrally defining an inlet for receivingpressurized fluid from the tube, an outlet bath for discharging thefluid from the body, a pressure reducing flow channel extending from theinlet for reducing a pressure and flow of fluid received at the inlet,and a pressure compensating chamber positioned between the pressurereducing flow channel and the outlet bath to receive fluid from thepressure reducing flow channel, the chamber being defined by a moveablefloor and at least one tapered baffle that separates the pressurecompensating chamber into an upstream portion and a downstream portionformed by an inner flow passage defined by the at least one taperedbaffle through which the fluid travels from the upstream portion;extruding a drip line tube having an inner surface and an outer surfacewith the inner surface defining an inner circumference of the tube; andconnecting the plurality of discrete elastomeric emitter bodies to onlya portion of the inner circumference of the inner surface of the tubeand at regular intervals therein.

Other methods contemplated herein relate to the emitters of FIGS. 28A-Jand 29A-H and include methods for manufacturing a pressure compensatingmember solely, as well as methods for manufacturing poly-materialemitters having pressure compensating members. For example, in oneinstance a method of manufacturing a pressure compensating member for apoly-material emitter comprising providing an elastomeric material, andmolding the elastomeric material into an elastomeric pressurecompensating member integrally defining: a flexible floor; side wallsextending substantially about a perimeter of the flexible floor andincluding an ingress opening and an egress opening; and at least onetapering baffle that separates the flexible floor and pressurecompensating member into an upstream portion and a downstream portionwith both the upstream portion and downstream portion having respectivevolumes or cross-sectional areas and the volume or cross-sectional areaof the upstream portion being larger than the volume or cross-sectionalarea of the downstream portion to assist the pressure compensatingmember in flushing grit therethrough. The method may further entailmolding a rigid emitter body such that the elastomeric pressurecompensating member is disposed within an opening defined by the rigidemitter body. In some forms, this method comprises molding the rigidemitter body to define a seat upon which the pressure compensatingmember is rested.

In other forms, methods of manufacturing poly-material emitters aredisclosed comprising providing a polyethylene and an elastomericmaterial, molding the polyethylene into a rigid emitter body integrallydefining an inlet, an outlet and a pressure reducing flow passageextending from the inlet, the rigid emitter body further defining a seatfor a pressure compensating member, molding the elastomeric materialinto a pressure compensating member integrally defining: a flexiblefloor; side walls extending substantially about a perimeter of theflexible floor and including an ingress opening and an egress opening;and at least one tapering baffle that separates the flexible floor andpressure compensating member into an upstream portion and a downstreamportion with both the upstream portion and downstream portion havingrespective volumes or cross-sectional areas and the volume orcross-sectional area of the upstream portion being larger than thevolume or cross-sectional area of the downstream portion to assist thepressure compensating member in flushing grit therethrough or throughthe emitter. Similarly, methods of manufacturing irrigation drip linetubes with such poly-material emitters are also contemplated. In someforms, a method of manufacturing an irrigation drip line tube includesproviding a polyethylene and an elastomeric material, molding thepolyethylene into a plurality of rigid emitter bodies each integrallydefining an inlet, an outlet, a pressure reducing flow passage extendingfrom the inlet, and a seat or socket, molding the elastomeric materialinto a plurality of pressure compensating members seated in the seat orsocket of the rigid emitter bodies, with each pressure compensatingmember integrally defining: a flexible floor; side walls extendingsubstantially about a perimeter of the flexible floor and including aningress opening and an egress opening; and at least one tapering bafflethat separates the flexible floor and pressure compensating member intoan upstream portion and a downstream portion with both the upstreamportion and downstream portion having respective volumes orcross-sectional areas and the volume or cross-sectional area of theupstream portion being larger than the volume or cross-sectional area ofthe downstream portion to assist the pressure compensating member influshing grit therethrough, and further extruding a drip line tubehaving an inner surface and an outer surface with the inner surfacedefining an inner circumference of the tube, and connecting theplurality of discrete elastomeric emitter bodies to only a portion ofthe inner circumference of the inner surface of the tube and at regularintervals therein.

Thus, it is apparent that there has been provided, in accordance withthe invention, an elastomeric emitter and methods relating to same thatfully satisfies the objects, aims, and advantages set forth above. Whilethe invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives,modifications, and variations will be apparent to those skilled in theart in light of the foregoing description. Accordingly, it is intendedto embrace all such alternatives, modifications, and variations as fallwithin the spirit and broad scope of the appended claims.

What is claimed is:
 1. A pressure compensating member for an emittercomprising: an elastomeric pressure compensating member integrallydefining: a flexible floor; side walls extending substantially about aperimeter of the flexible floor and including an ingress opening and anegress opening; and at least one tapering baffle that separates theflexible floor and pressure compensating member into an upstream portionand a downstream portion with both the upstream portion and downstreamportion having respective volumes or cross-sectional areas and thevolume or cross-sectional area of the upstream portion being larger thanthe volume or cross-sectional area of the downstream portion to assistthe pressure compensating member in flushing grit therethrough.
 2. Thepressure compensating member of claim 1 wherein the side walls includefirst, second, third and fourth side walls positioned in a generallyrectangular orientation, with the first and second side walls positionedparallel to one another and having a generally flat upper surface, andthe third and fourth side walls positioned parallel to one another andgenerally transverse the first and second side walls, with the third andfourth side walls having a curved upper surface with a first radius ofcurvature that corresponds to an interior surface of an irrigation driptube.
 3. The pressure compensating member of claim 2 wherein theflexible floor has a first side upon which the at least one taperingbaffle is connected, and a second side located opposite the first side,and wherein the flexible floor is shaped so as to be concave on thesecond side and convex on the first side, the flexible floor have asecond radius of curvature that corresponds in shape to the first radiusof curvature of the upper surfaces of the third and fourth side walls.4. The pressure compensating member of claim 3 wherein the first,second, third and fourth side walls extend above the first side of theflexible floor and terminate in the generally flat upper surfaces of thefirst and second side walls and the curved upper surfaces of the thirdand fourth side walls, and the first, second, third and fourth sidewalls extend below the second side of the flexible floor and terminatein generally flat and coplanar bottom surfaces.
 5. The pressurecompensating member of claim 1 wherein the elastomeric body furtherdefines a protruding portion proximate at least one of the ingressopening and/or the egress opening.
 6. The pressure compensating memberof claim 5 wherein the elastomeric body defines a first protrudingportion aligned with the ingress opening and a second protruding portionaligned with the egress opening and the first and second protrudingportions extend out beyond a boundary defined by the side walls.
 7. Thepressure compensating member of claim 6 wherein second protrudingportion extends out further from the boundary defined by the upstandingwalls further than the first protruding portion.
 8. The pressurecompensating member of claim 3 wherein the side walls include at least afirst side wall and a second side wall and the at least one taperingbaffle comprises a first tapering baffle extending from the first sidewall and a second tapering baffle extending from the second side wall,with the first and second tapering baffles extending toward a center ofthe flexible floor and toward one another to define the upstream portionand downstream portion of the pressure compensating member.
 9. Thepressure compensating member of claim 8 wherein one of the first andsecond tapering baffles extends further toward the center of theflexible floor than the other of the first and second tapering baffles.10. The pressure compensating member of claim 1 further comprising arigid emitter body defining a seat within which the pressurecompensating member is disposed to form a poly-material emitter.